Lap trinh C++ - FINAL

7/26/2019 Lap trinh C++ - FINAL

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Lp trnh C++

GV: Trn Hu Quc Th Trang 2

LP TRNH C++y l nhng ni dung c bn SV cn nm vng:

Chng I: Gii thiuTin hc i cng (hay lp trnh C++), ni chung tinh thn ca mn hc

l cng da phn ln vo cch lp trnh m chng tng nghin cu tin hci cng A1 (lp trnh Pascal). V vy a s nhng lnh c trong pascal chngta s gp li trong ngn ng C++, mc d c mt s im sai khc (nh cu

php), nhng nhn chung mc ch ca nhng lnh hon ton ging vi ngnng Pascal m chng ta hc . i vi nhng tp lnh ny chng ta s khngnghin cu chi tit v mt l thuyt, m ch yu tp trung vo phn thc hnh,vn dng (c th dng phn mm chuyn ngn ng t pascal sang C++ hiu r hn- download ti http://fit.hcmup.edu.vn/~thqthu).

Ring vi nhng tp lnh c th ring ca C++ chng ta s nghin cuk hn v phn l thuyt.

+ Ngn ng lp trnh: C+++ Mi trng lp trnh: Visual C++ 6.0 hoc Dev-Cpp

+ B gip ngn ng (help): MSDN 2001


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1.1.To v bin dch mt chng trnh C++ trn mi trng Visual C++Phn tch v d n gin: Chng trnh Hello World

Kt qu xut ra mn hnh (Bm phm CTRL + F5, hoc F5)

Chthch

Chy chng trnh

Khai bo thvin ca lnh

std::cout

Lnh xut chui ramn hnh

Lnh xunghng

Ni thng boli , n u c l i

bm F4tm li

Hm main:Chng trnh lun b t

u t y

Ni bo cnh bo: cnh bo

khng lm nh hng n vicchy ct, tuy nhiu i vi mts cnh bo quan trng ta nn

kim tra k


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Mt s yu cu khi trnh by son tho mt chng trnh (bt buc)

Tab

Ni khai both vin vhm main cchnhau 1 dng

Cc dng lnh c ngha khc nhaunn cch nhau 1dng

S dng phmTab lngcc dng lnhvi nhau

Nn c ch thch cc dng lnhquan trng


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1.2 Lm quen vi mi trng lp trnh Visual C++ 6.0

1. Chy chng trnh Microsoft Visual C++ 6.02. Vo File -> New


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3. Ti th Projects,chn Win32 Console Application,nh tn bi lm voproject name( y l BaiLamQuenVC6), chn ni lu tr bi Location( y chn lu D:\BaiLamQuenVC6) => ok


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4. Chn An empty project, nhnfinish , nhn ok

5. Vo File -> New


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6. Ti th File, ta chn C++ source file, v nh tn file vo File Name(y l FileSource) (Ch nhng vng mu )


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7. G ni dung chng trnh Hello World

8. Bin dch: vo Build-> Rebuild All


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Quan st cui mn hnh, nu bin dch thnh cng ta s thy dng ch 0

error(s), 0 warning(s). Nu khng thnh cng th cn xem li on m

mnh g vo ng cha, bm F4 tm li

Lu :Mt thi quen tt l nn ghi li v hiu cc dng bo li lnsau c th t sa li.

9. Chy chng trnh, bm Ctrl + F5(hoc F5, nu bm F5 Mn hnh chychng trnh c th hin th ri tt rt nhanh, do cn quan st k.)

Lu quan trng:1. Trong mt chng trnh:

-Hm main l ni chng trnh bt u.

-Mt chng trnh ch c mt hm main duy nht

2. Khi vit xong mt chng trnh, vit tip chng trnh khc, ta phi

ng chng trnh trc i bng cch vo menu File - > Close Workspace

3 . m mt chng trnh c sn, trong mi trng VC6++, vo File ->

OpenWorkspace ri chn file *.dsw

4. Trong th mc cha chng trnh, ta lun c 1 th mc Debug, trong th

mc ny c mt file *.exel file chy trc tip, cn nhng file khc l nhngfile bin dch khng quan trng, ta nn xo chng khi copy t my trng vnh hoc np bi tp cho gio vin.


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Chng 2: Bin v Kiu d liu

2.1. Kiu d liu:a. Cc loi d liu thng dng:

Tn kiu d liu Phm vi ngha V d

int -32768 -> 32767 Kiu s nguyn -2

unsigned int 0 -> 65535 S nguyn khng m 5

long -2147483648->2147483647 S nguyn di 3445

float S thc 4.5

double S thc 7.8

char -128 -> 127 K t A, +

unsigned char 0 -> 255 K t B,-

bool true, false Kiu logic

Ch :

- Kiu k t cng c th l mt dng ca kiu s nguyn

- Kiu bool L kiu th hin gi tr ng sai

+ C hai gi tr: true hoc false

+ Cc php ton:

&& php AND (v)

|| php OR (hoc)

! php NOT (ph nh)

b. Kiu d liu do ngi dng nh ngha

- T kho: typedef

- C php: typedef tn_kiu_c tn_kiu_mi

- ngha: sau khi khai bo, ta c th s dng tn_kiu_mi nh mt

kiu d liu bnh thng khc.


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V d:

- nh ngha li tn kiu d liu s nguyn

typedef int so_nguyen;

Khi khi so_nguyenl mt kiu d liu nh kiu int

2.2. Bin: nh ngha - Cc thnh phn ca bin - Khai bo bin- Mi bin cn phi khai bo trc khi s dng.

- Vic khai bo bin c thc hin theo c php sau:

Kiu_d_liu tn_bin;

Kiu tn_bin = gi_tr_ban_u_ca_bin;

Kiu tn_bin1, tn-bin2,...;

V d:int i, j; //i v j l 2 kiu s nguyn

char a; //a l kiu k t

float f; // f l kiu s thc

- Lu :

+ Mt tn hp l l mt dy ca cco Ch (hoa v thng)

o S (Mt tn khng c bt u bi s)

o Du ni di (Khng nn bt u bng du ni di)

+ Cc tn c phn bit ch hoa v ch thng

V d: Bien1 khc vi BIEN1

+Tn bin khng c trng vi tn ca cc lnh, cc t khotrong C++ (v d khng c t tn bin l int, return, cout,...)

2.3. Biu thc v ton t: Biu thc - Ton t v u tin ca ton tTn ton t ngha V d

+ cng a+b

- tr a-b

* nhn a*b


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/ chia a/b

% chia ly phn d a%b

> a>b

< a


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2.4. Cu lnh gn: C php - Thi hnh cu lnh gnC php: tn_bin = biu thc (hoc bin);

ngha:

Gi tr ca bin bn tri du = s bng gi tr ca biu thc sau

khi tnh ton xong(hoc gi tr ca bin) bn phi du =

V du:

int i, j ; //khai bo bin i v j l kiu s nguyn

i = 3; // i s c gi tr l 3;

j = i +7; // j s c gi tr l 10 ( 3 + 7)

Lu :

So snh php ton a++vi ++a(tng t cho a--v -- a)

V du:

/* khai bo bin a v b l kiu s nguyn v cng c gi tr ban u l 5

*/

int a = 5;

int b = 5;int i,j; //khai bo bin i v j

i = ++a; ngha:

- Thc hin php ton a=a+1 trc, tc gi tr a tng

ln 1 n v, hay a s c gi tr l 6

- Sau i s c gn gi tr 6 ca a

- Gi tr ca a sau lnh ny s c gi tr l 6j = b++; ngha:

- Thc hin php gn j=b trc, do gi tr ca b hin

gi l 5, nn j s c c tr l 5

- Sau php ton b=b+1 s c thc hin, tc gi

tr ca b s c tng ln 1 n v, khi b s c gi tr

l 6


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2.5. Chuyn i kiu (p kiu)p kiu l mt th thut kh hay dng bin i kiu ca mt bin,

hay mt biu thc sang mt kiu d liu ph hp vi nhu cu tnh ton ca

chng trnh.

C php: (tn kiu mi) tn_bin(hoc biu thc);

Lu : gi tr ca php p kiu s chuyn gi tr sang kiu d liu

mi, nhng kiu d liu ca nhng bin tham gia vo php p kiu vn

khng b thay i kiu d liu

V d 1:

1.34 : l mt s thc, thuc kiu s thc

(int) 1.34 : gi tr c p kiu sang kiu s nguyn, khi kt

qu s l 1

V d 2:

float i = 2.34; /* i c khai bo l kiu s thc, vi gi tr ban

u l 2.34 */

int j = (int) i ; // p kiu khi j s c gi tr l 2, tuy nhingi tr ca i vn l 2.34


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Nhng lu quan trng:

Tt c lnh u kt thc bng du chm phy ;

Cch ch thch:

o Ch thch 1 dng: dng k hiu //

o Ch thch nhiu dng: dng k hiu m /* v k kiu ng */

V d:

/*y l dng ch thch dng 1

y l dng ch thch dng 2 */

Mt s k t c bit:

\n l m xung dng

\tl m du Tab

\ l m du nhy kp

\\l m du \

Chui: bt u v kt thc bng du v

o V d:

y l mt chui

y l mt chui c xung dng \n


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2.6Lnh xut/nhp chun:

Mt s lnh c bn cn nm

- std::cout (xut d liu ra mn hnh)

V d:

std::cout


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getch(); //Dng mn hnh

return 0;

}


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Chng 3: Cu trc iu kin

3.1. iu kin if:a. C php:

1. if (BT lgic)

{

................ //Khi lnh

}

2. if (BT lgic)

{

.................... //Khi lnh 1

}

else

{

.................... //Khi lnh 2

}

BT lgic

Khi lnh

true false

Khi lnh 2

BT lgic

Khi lnh 1

true false


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3. if (BT lgic)

{

.................... //Khi lnh

}else

if (BT lgic)

{

............. //Khi lnh

}

b. Bi tp:i. Bi tp 1: Nhp vo mt s x, xc nh tnh chn l ca x

ii. Bi tp 1: Nhp vo mt s x, xc nh s x l s dng, hay s m

hoc bng 0 ?

iii. Bi tp 2: Nhp vo 2 s nguyn a,b. Tm s ln nht.

iv. Bi tp 2: Nhp vo 3 s nguyn a,b,c. Tm s ln nht v s nh

nht trong 3 s .

Ch :

+ C++ qui c:

true != 0

false == 0

+ Kiu Logic:

L kiu th hin gi tr ng sai C hai gi tr: true hoc false Cc php ton:

&& php AND (v) || php OR (hoc) ! php NOT (ph nh)


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v. Gii phng trnh Ax + B = 0. Vi A, B l hai h s c nhp vo

t bn phm

vi*. Nhp vo mt s n, xc nh xem c phi l s chnh phng hay

khng?


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3.2. Cu trc la chn switch case a. Trng hp s dng Khi c qu nhiu la chn dn n nu dng cu trc if else

if s di dng v kh hiu. Khi s so snh ch l so snh bng, khng phi so snh th t.

b. C php:switch(biu thc nguyn){

casetrng hp 1:Cc cu lnh 1;break;

casetrng hp 2:Cc cu lnh 2;break;

default:

Cc cu lnh n;break;

}

Lu :- Biu thc nguyn: Bin kiu nguyn, biu thc c gi tr nguyn, hoc

kiu k t, kiu logic.- Trng hp ... : l s nguyn, hng k t, hoc biu thc hng, gi tr

logic.- default: (trng hp ngoi l), s c thc thi nu cc trng hp

trn khng xy ra (thnh phn khng bt buc).

c. Bi tp:

Bi tp 1: Nhp vo mt s x, xc nh tnh chn l ca x

Bi tp 2: Vit chng trnh cho tr chi thi trc nghim

- Xut ra mn hnh mt cu hi v 4 p n a, b, c, d.

- Nu ngi chi chn p n sai th xut cu thng bo sai ri

- Cn nu ngi chi chn p n ng th bo ng ri

Biu thc= TH1

exit

true Cc cu lnh 1

true

false Cc cu lnh n(default)

Biu thc= TH2

Cc cu lnh 2

false

break

break

break

Khng break

Khng break


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Bi tp 3: Xut kt qu ca php ton

A php_ton B

Vi A, B l 2 s thc nhp t bn php

V php ton l mt trong nhng php ton sau: +, -, *, /

Bn hy vit chng trnh xut ra kt qu ca php ton trn ph

hp vi php ton m ngi dng nhp vo.

V d:

Ngi dng nhp A = 2

B = 3.5

Php ton: *

Khi kt qu ca php ton l: 2 * 3.5 = 7


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Chng 4: Cu trc lp4.1. Cc cu trc lp:

1. while (BT lgic)

{

................ //Khi lnh

}

2. do

{

................ //Khi lnh}while (BT lgic);

Lu :

-c du ; cui lnh while

- Khi lnh lun c thc hin t

nht 1 ln

BT lgic

//khi lnh

true false

BT lgic

//khi lnh

true

false


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3. for (khi to; iu kin; lnh thchin sau)

{........... //Khi lnh

}

V d:for(int i=0; i< 5; i++)

cout


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- continue (thng thy trong vng lp for): Trong vng lp khi gp t

kho ny th chng trnh bt u mt vng mi ca vng lp.

4.2. Mi lin quan gia for v while:a. Chuyn lnh for thnh while:

Khi_to_for;

while (iu_kin_ca_for)

{

.... //Khi lnh trong thn lnh for

Lnh_thc_hin_sau_ca_for;

}

b. Chuyn lnh while thnh for:for ( ; iu_kin_ca_while; )

{

..... //Khi lnh trong thn lnh while

}

2. Bi tp:Thc hin bng cu trc while, do... while, for cho c 3 cu i, ii, iii

i. Tnh tng 1 + 2 + 3 + 4 + ... + n

ii. Tnh tng 1 + 1/2 + 1/3 + 1/4 + ... +1/ n

iii.Tnh tng 12+ 22+ 32+ 42+ ... + n2

iv.Nhp vo mt s n, xc nh xem c phi l s nguyn t khng?

v. Xut ra cc s nguyn t t 1 n n, vi n l s nguyn dng nhp t bn

phm


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Chng 5: Cu trc

5.1. Nhc li cch khai bo mt kiu d liu mi (typedef):a. C php:

typedef Kiu_d_liu_c Kiu_d_liu_mi;

b. ngha:

Khi khai bo mt kiu d liu mi bng typedef, tc l

Kiu_d_liu_mi l 1 kiu d liu nh kiu Kiu_d_liu_c

Ta c th s dng kiu d liu mi nh nhng kiu d liu bnhthng khc (s dng ging nh kiu d liu int, float, double,

char, )

c. V d:

typedef int so_nguyen;

so_nguyen i;

int j;for (so_nguyen t = 0; t


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b. C php:

i. Cch 1: dng tyedef nh ngha kiu mi

typedef struct{

kiu_d_liu trng_1;

kiu_d_liu trng_2;

.....

}tn_cu_trc;

ii. Cch 2: khng dngtyedef nh ngha kiu mi

struct tn_cu_trc{

kiu_d_liu trng_1;

kiu_d_liu trng_2;

.....

};

khai bo tn cu trc ng thi c th khai bo cng lc cc

bin kiu cu trc.

struct tn_cu_trc{

kiu_d_liu trng_1;

kiu_d_liu trng_2;

.....

}bin_1, bin_2,...;

Lu :

- C du chm phy (;) cui khai bo cu trc- Ta s dng kiu cu trc nh mi kiu bnh thng khc


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c. V d:

Xy dng kiu cu trc PHN S, vi 2 trng l T v MU kiu s

nguyn

Cch 1:

typedefstruct

{

int tu;

int mau;

} PHANSO;

Cch 2:

struct PHANSO

{

int tu;

int mau;

};

khi ta c th s dng kiu cu trc PHANSO nh l mt kiu bnh

thng

PHANSO ps;

c. Cch truy cp vo cc trng ca cu trc:

Ta dng c php sau truy cp vo trng ca cu trc

Tn_bin_kiu_cu_trc.trng

(lu : c du chm (.) ngn cch gia bin_kiu_cu_trc v trng

c gi)V d, vi cu trc PHANSO c khai bo nh trn, ta c th nhp v

xut cc trng ca bin ps c kiu cu trc PHANSO nh sau:

PHANSO ps;

cin>>ps.tu>>ps.mau;

cout


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5.2. Bi tp cu trc1) Vit chng trnh nhp vo 2 phn s ps1, ps2

o Tnh tng, hiu, tch, nhn 2 phn s , kt qu tr v l

phn s

(Lu : phi kim tra tnh ng n ca d liu nhp vo, v d mu

ca phn s phi lun khc khng)

2) Vit chng trnh nhp vo 3 im A, B, C trong h trc ta Oxy,

hy:

o Kim tra xem 3 im c thng hng hay khng

o Tnh khong cch t A n B, A n C, v B n Co Nu A,B,C khng thng hng hy tnh din tch, chu vi ca

tam gic ABC

3) Vit chng trnh qun l im ca sinh vin, vi

o S lng sinh vin l n, vi n nhp t bn phm

o Thng tin v sinh vin gm:

H v tn Ngy thng nm sinh

MSSV

im Ton, L, Ho

im trung bnh


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Chng 6: Mng6.1. nh ngha:

Mng l mt tp hp nhiu phn t c cng mt kiu gi tr v c cng

chung mt tn

6.2. Khai bo:

Kiu_d_liu Tn_mng[spt][spt]....;

C th:

a. Mng mt chiu:

Kiu_d_liu Tn_mng[spt];b. Mng hai chiu:

Kiu_d_liu Tn_mng[spt dng][spt ct];

V

d:

-

Mng

1

chi

u kiu s nguyn c 10 phn t: int a[10];

a[0] a[1] a[2] a[3] a[4] a[5] a[6] a[7] a[8] a[9]

- Mng 1 chiu kiu k t c 5 phn t:char s[5];

//Lu : y cng c th xem l mt chui c 5 k t

- Mng 1 chiu kiu chui c 5 phn t: string chuoi[5];

- Mng 2 chiu kiu s nguyn c 3 dng, 4 ct: int a[3][4];

a[0][0] a[0][1] a[0][2] a[0][3]

a[1][0] a[1][1] a[1][2] a[1][3]

a[2][0] a[2][1] a[2][2] a[2][3]

Lu quan trng:

- Ch s ca mng lun lun c nh t ch s 0

- Cc phn t ca mng ta c th s dng nh mt bin bnh thng

V d: Gn mt phn t ca mng cho 10

a[2] = 10;


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6.2. Bi tp:

i. Thc hin cc php ton ca mng (1 chiu v 2 chiu):

- Khi to mt mng

- Xut cc gi tr ca mng

- Thm mt phn t vo mng (1 chiu)

- Xo mt phn t trong mng (1 chiu)

ii.Nhp vo thng tin ca mt sinh:

- H tn

- Nm sinh

- im cc mn hc (lu vo mng)

Xut ra im trung bnh ca sinh vin

iii.Nhp vo mt dy s nguyn, tm phn t ln nht, nh nht ca dy (1

chiu, 2 chiu)

iv.Nhp vo mt dy s nguyn,

Xut ra 2 dy s:

- Dy nhng s m ca mng

- Dy nhng s dng ca mng

v.Nhp vo mt dy s nguyn,

Xut ra 2 dy s:

- Dy nhng s nguyn t

- Dy nhng s chnh phng.


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Chuyn : Mng k t - chui

1. K t- V d: c , b, d- Tn kiu d liu: char- V d:

char c;cin >>c;

2. Mng- L mt tp hp cc bin c cng kiu d liu- T phn t ca mng ta c th xem l mt bin, v d a[i], a[1],

a[2][3],.... ta c th thc hin mi lnh, mi php ton trn bin pdng vo t phn t ca mng

- Lu : Mng lun lun c nh s t 0- Cch khai bo:

Mng 1 chiu:Tn_d_liu Tn_mng[spt];

Mng 2 chiu:Tn d liu Tn_mng[s_dng][s_ct]

- V d:int n;

int a[100]; //Khai bo mng 1 chiu kiu s nguyn c 10 phn t

cout


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- Khai bo: char tn_chui[chiu_di_chui];- Vi char s[10] = Hello th s[0] = H, s[1] = e, s[2] = l,

s[3]=l, s[4]=o, c bit s s c thm k t kt thc chui ls[5] = \0. Khi chiu di chui l 5 (khng tnh k t ktthc chui)

- V d:char s[10]; //khai bo mt chui c ti a 10 k t//hay mt mng gm 10 phn t kiu k t

- Nhp d liu vo chuii. Cch 1:Nhp t phn t ging nh mng

//Vi L l chiu di ca chuifor (int i = 0; i < L; ++i)

cin>>s[i];

ii.Cch 2:Nhp chui khng ckhong trngcin>>s;

iii.Cch 3:Nhp chui ckhong trnggets(s);

- Cch xut chuii. Cch 1: Xut t phn t ging nh mng

//Vi L l chiu di ca chuifor (int i = 0; i < L; ++i)

cout


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int atoi(const char* s) i chui s sang s nguyn (nukhng i c kt qu s tr vgi tr 0)V d:

char s[10] = 123;int i = atoi(s);cout


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Lu :-Cch khai bo hng:(hng l nhng bin l gi tr s khng bao gi b

thay i trong chng trnh)+ Cch 1: (dng macro #define)

#define bin_hng gi_tr //Khng c du ; cui lnh

- ngha: nu dng t kho marco #define, trong khi bin dch,chng trnh s thay tt c bin_hngbng gi_tr- V d:

#define bien_hang 123+ Cch 2:

const kiu_d_liu tn_hng = gi_tr; //c du ; cui lnhV d:

const int bien_hang = 123;

-

Khi lp trnh trn mi trng Visual C++, trong khi nh lnh ta c thdng phm nng Ctrl + Space bar hin th cc lnh ca trong C++

-

Dng phm nngCtrl+ space barhin lnh


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Do hm getline trong Visual C++ b li, ta s sa li bng cch sau:+ Bc 1: Bm chut phi ln ch khai bo th vin , bm chut

phi chn Open Document

+ Bc 2: Bm phm nng Ctrl + F+ Bc 3: g vo hp thoi tm kim dng ch:

else if (_Tr::eq((_E)_C, _D))


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+ Bc 4: Thay i mt s lnhBan u Sau khi sa

else if (_Tr::eq((_E)_C, _D)){_Chg = true;

_I.rdbuf()->snextc();

break; }

else if (_Tr::eq((_E)_C, _D)){_Chg = true;//_I.rdbuf()->snextc();

//Phn thm vo_I.rdbuf()->sbumpc();break; }

+ Bc 5: Bm Ctrl + S (lu ni dung thay i), sau ng ca sli.


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Bi tp b sung:

1. Nhp vo mt mng 2 chiu n x n (ma trn vung) Tnh tng cc s hng trn ng cho chnh Tnh tng cc s hng trn ng cho ph Duyt phn na trn ca ng cho chnh

2. Sp xp tng dn/gim dn cc gi tr ca mt mng 1 chiu3. Bi tp v phn s

Nhp vo 2 phn s (phn s gm c t v mu) Tnh tng, hiu, tch, thng ca 2 phn s Rt gn phn s

4. Xut ra mn hnh cc hnh sao (vi chiu cao ca mi hnh l mt s nguyndng h c nhp t bn phm)

***************

***

*******

*****

****

*****

*******

***************

*

5. Nhp vo mt chui s v mt k t c, kim tra xem trong s c k t c khng,nu c th xut v tr ca c trong s, nu khng xut ra gi tr -16. Tng t nh bi tp 4, nhng thay v l k t c, ta s thay bng mt chui s2

h


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Chuyn :H tr k thut lp trnh

A. Phm vi hot ng ca mt bin1. Phn loi bin:

- Bin ton cc: L nhng bin c phm vi hot ng xuyn sut t u

n cui chng trnh

- Bin cc b:

+ L nhng bin c phm vi hot ng ti mt thi im ca

chng trnh.

+ Phm vi hot ng ca bin cc b l t lc khai bo bin cho

n du ng khi gn nht cha n.

2. Ni khai bo bin:

- Bin ton cc: khai bo ngoi hm main

- Bin cc b: khai bo trong hm main

B. Debug

1. Phn loi cc loi li (Error):

- Li c php: L nhng li do ngi lp trnh khng ghi ng c php

lnh, nhng li ny s c chng trnh bin dch thng bo.

Ni thng boli c php ,

nu c libm F4

tm liNi bo cnh bo: cnh bo

khng lm nh hng n vicchy ct, tuy nhiu i vi mts cnh bo quan trng ta nn

kim tra k


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- Li logic: L nhng li chng trnh do ngi lp trnh vit khng thc

hin ng vi ni dung yu cu c t ra (v d: yu cu ca bi ton, yu cu

ca khch hng,...)

2. Debug l g?:

-L cch tm nhng li logic bng cch chng trnh chy tng dng

lnh (chy tng bc t trn xung), qua tng dng lnh ta s xc nh gi tr

ca tng bin thay i nh th no c ng vi thut ton a ra hay khng =>

t ta c th xc nh c li logic ca chng trnh.

3. Cch hot ng ca Debug:

Bc 1: t nhng im dng breakpointbng bm phm nng F9

(breakpoint s nh du nhng dng lnh, khi chng trnh s

dng li ti nhng dng lnh cha breakpoint)

i vi nhng li logic chng ta phi s dng Debug tm ra li.

im dngbreakpoint

im dngbreakpoint


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Bc 2: Bm F5 chng trnh s bt u ch Debug (chng trnh s

dng li v tr breakpoint).

Tu theo mc ch ca ngi kim tra li, ta c cc phm nng h

tr

+ F10: chng trnh chy tng bc, b qua chng trnh con

+ F11: chng trnh chy tng bc, nu gp chng trnh con s

vo kim tra (khng b qua chng trnh con).

+ F5: n im dng breakpoint gn nht

+ F9: thm im dng breakpoint

+ Shift + F5: Dng ch Debug

Lu :

1 .Mn hnh trong ch debug gm 3 ca s chnh

2. Ctrl + F5: chy chng trnh khng Debug

F5: chy chng trnh ch Debug

Dnglnh angkim tra

Ca s kimtra gi tr bin(do chngtrinh bindch qun l)

(ca s quickwatch) Cas kim tra gi tr bin (do

ngi lp trnh qun lbng cch nhp tn binvo).

Nu khng c, bm Shift +F9 (vo menu Debug ->quickwatch..)


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for (i = 0; i < n; i++)

cout


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for (i = 0; i < n; i++)

cout


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for (i = 0; i < n; i++)

cout


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Lp trnh C++


b. Hm khng c gi tr tr v:C php:i. Hm khng c truyn tham s

C php V dvoidtn_hm()

{ //Khi lnh;}

void Hm_Cho()

{ cout


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7.3. Khai bo hm khai bo prototype:C php:

void Tn_Hm(danh sch kiucc tham s);kiu_tr_v Tn_Hm(danh sch kiucc tham s);

Ch : - Danh sch kiu tham s: ch ra cc kiu ca tham s (c th choc khng c tn bin)

V d://Khai bo prototype

void Xuat_Tong(int , int ) ;void main(){

//Khi lnh trong hm main}

//nh ngha hmvoid Xuat_Tong(int a, int b){

int s = a + b;cout


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7.4. Li gi hm:a. V d vi hm khng c gi tr tr v

//Khai bo prototypevoid Xuat_Tong(int , int ) ;

void main(){Xuat_Tong( 2 , 3 ); //Gi hm Xuat_Tong

}

//nh ngha hmvoid Xuat_Tong(int a, int b){

int s = a + b;

cout


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Tng t ta c s so khp nh sau:Hm int Tinh_Tong(int a , int b)

Li gi hm i = Tinh_Tong( 2 , 3 );

Hay ti thi im gi hm Xuat_Tong a s c gi tr 2, b s c gi tr l 3V gi tr 5 s c tr vcho bin i, khi i s c gi tr l 5

7.5. Tham tr v tham chiu (quan trng):Tham tr Tham chiu

- khi khai bo khng c du &giakiu v tham sV d:void ham(int a){

//Khi lnh}

- khi khai bo c du & gia kiu vtham s

void ham(int&a){

//Khi lnh}

- Khng lm thay ibin c gi - Lm thay ibin c gi

void binh_phuong(int );

void main(){

int i = 5;binh_phuong( i );cout


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7.6. Gi tr mc nh ca tham s:a. ngha:

Cho php gi hm mt cch linh hot:- Nu c truyn tham s th hm s ly tham s c truyn- Nu khng c truyn tham s th hm s ly gi tr mc nh

b. Cc khai bo:Ta ch cn khai bo cc gi tr mc nh ca tham s lc khai boprototype (khai bo hm)

V d 1:int Tinh_Tong(int , int b = 1); //Gi tr mc nh ca b l 1

int main(){

int i;i = Tinh_Tong ( 2 , 3);cout


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7.7. Qu ti hm:a. Cc thnh phn ca hm:

Hai hm khc nhau khi chng c t nht 1 trong 3 thnh phn khc nhau,gm:

o Tn hm

o Kiu ca tham so S lng tham s

b. Qu ti hm:Qu ti hm l nhng hm c cng tn hm, nu ri vo 1 trong 2 trnghp sau:

o S lng tham s khc nhauo Cng s lng tham s, khc nhau mt kiu d liu no ca

tham s

V d 1:void Xuat_Tong(int a, int b);void Xuat_Tong(int a, int b, int c);

int main(){

Xuat_Tong( 1 , 2);

Xuat_Tong( 1 , 2, 3);}

void Xuat_Tong(int a, int b){

cout


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7.8. Qu ti ton t:a. Cc ton t trong C++:

Cc ton t quen thuc trong C++Ton t V d

+ a = b + c;

- a = b c;* a = b * c;/ a = b / c;

% a = b % c;= a = b;

== if (a == b){}[] a[1]; //vi a l mng>i;

Cc ton trong C++ u c chung mt cch t tn hmtheo m t sau:operator

b. Qu ti ton t:ng dng: ta c th s dng cc ton t ca C++ i vi cc bin cu

trc m ta t ngha nh nhng kiu bnh thng trong C++V d:

vi kiu cu trc PHNS c khai bo nh sau:

struct PHANSO{int x;int mau;

};

int main(){

PHANSO ps1, ps2;

cin>>ps1>>ps2; //Nhp nh kiu d liu bnh thng

PHANSO ps;ps = ps1 + ps2; //Thc hin php cng nh kiu d liu

//bnh thng khc

cout


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V d:1. Qu ti ton t + ca 2 phn s

PHANSO operator + (PHANSO a , PHANSO b){

PHANSO ps;

ps.tu = a.tu * b.mau + a.mau * b.tu;ps.mau = a.mau * b.mau;return ps;

}

2. Qu ti ton t


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Bi tp v hm:

1. S dng hm v qu ti hm, qu ti ton t vit li bi tp phn sa. kim tra tnh ng n ca phn s

b.Nhp / Xut phn s

c. Rt gn phn sd. Cng tr nhn chia phn se. Qu ti ton t nhp, xut, = , ==, +, - , *, /

2. S dng hm v qu ti hm, qu ti ton t vit li bi tp v mng 1chiu kiu s nguyn

a.Nhp / xut mng 1 chiub. Tm cc s nguyn t trong mngc. Tm cc s chnh phng trong mng

d.

Thm 1 phn t vo u dye. Thm 1 phn t vo cui dyf. Thm 1 phn t vo v tr kg. Xo 1 phn t v tr kh. Tm kim phn t c gi tr xi. Tm min

j. Tm maxk. Tnh tngl. Tnh trung bnh cc s hngm.o ngc dyn. Sp xp theo th t tng/gim

3. S dng hm v qu ti hm, qu ti ton t vit li bi tp v mng 2chiu kiu s nguyn

a.Nhp / xut mngb. Thm 1 dng vo u ma trnc. Thm 1 phn t vo cui ma trnd. Thm 1 phn t vo dng th ke. Xo dng th kf. Tm min

g. Tm maxh. Tnh tngi. Tnh trung bnh cc s hng

j. Tm kim phn t c ga tr x


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Lp trnh C++


Chng 8:T chc th vin

8.1. ngha ca vic t chc th vin:Khi lp trnh, lp trnh vin lun c xu hng s dng li nhng hm m

mnh vit, khng phi tn cng vit li nh ban u. V vy h t chc cc

hm thng s dng li thnh th vin, khi no cn s dng li th ch cn

gi hm ra, m khng cn phi nh ngha li hm.

8.2.Cc bc to th vinCc bc to th vin mang tn tenthuvien

i. Giai on 1: To file tenthuvien.hBc 1: Vo menu Project -> Add to project -> NewBc 2: Ti ther File, chn C/C++ header fileBc 3: nh vo: tenthuvien.h vo file name

Bc 4: bm OK

Tn th vin, trongv d ny th vin

c tn l:Tinh_tong


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Bc 5: Khi ta c mt file l tenthuvien.h , trong flie ny tason ni dung nh sau:

- u file:#ifndef __TENTHUVIEN_H__#define __TENTHUVIEN_H__

- Gia file:- Khai bo hm (prototype ca hm) ca cc hm m ta munt chc thnh th vin

- Cui file:#endif

ii. Giai on 2: To file tenthuvien.cppBc 1: Vo menu Project -> Add to project -> NewBc 2: Ti ther File, chn C/C++ Source FileBc 3: nh vo: tenthuvien.cpp vo file name

Sau chn okBc 4: Khi ta c mt file l tenthuvien.cpp , trong flie ny tason ni dung:

-u file:#include tenthuvien.h

-Cc nh ngha hm c khai bo trong tenthuvien.h

iii.Giai on 2: S dng th vin tenthuvien nhng file no c s dng cc hm trong th vin

tenthuvienta u phi khai bo th vin u file#include tenthuvien.hSau ta c th s dng cc hm trong th vin mt cch

bnh thng nh cc hm trong C++.


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8.3.Phn tch v dV d ta c chng trnh tnh tng 2 s a v b c vit mt cch bnh

thng nh sau:

Vit li chng trnh trn vi cch t chc th vin xy dng th vinTnh_tong

i. Ni dung file Tinh_tong.h


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ii.Ni dung file Tinh_tong.cpp

iii.Ni dung file s dng th vin Tinh_tong

8.4.Ch th #include: so snh 2 cch khai bo th vin

#include #include th_vin.hChng trnh s tm th_vin trong thmc mc nh cha cc th vin trongC++

- Chng trnh s tm th vin trongth mc gc (nn ct ang chy)- Nu khng tm thy th vin, chngtrnh s tm trong th mc mc nhcha cc th vin trong C++

Thng l cc th vin chun ca C++ Thng l cc th vin do ngi lptrnh t nh ngha


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Bi tp:Vit li cc tt c bi tp trong chng hm (chng 10) bng cch t

chc thnh th vin


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Chng 9: Qun l b nh ng9.1. Khi nim v nh - a ch trong lp trnh:

Khi ta khai bo mt bin, iu c ngha l chng trnh s to cho

ta mt nh lu tr bin .

int main(){

int a;int b;int c;

a = 10;

b =20;c = 30;

return 0}

8 30 c4 20 b0 10 a

a chGi tr hinthi ca

nhbin

Mt nh gm c 2 thnh phn c bn sau:- a ch ca nh (do h iu hnh qun l)- Gi tr hin thi ca nh

Vi mt bin a, ta mun bit a ch nh lu tr ca n l bao nhiuth ta dng ton t & xc nh a ch.

V d:int a = 20;cout


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9.3. Cc thao tc trn con tr:i. Con tr lu a ch nh, nn

cout


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Bin tnh Bin ng

Kch thc c nh khng c nh

Phm vi s dng t lc khai bo n htkhi gn nht cha n.

t lc c to ra v ktthc khi b hy.

Tn ca bin dng

Lu gi tr Lu a ch

Cch truy xut gi tr tn_bin *tn_bin

Cch truy cp a ch & tn_bin tn_bin

T ng gii phng khiht phm vi s dng

Khng t ng giiphng. Lp trnh vinphi lo vic ny.

9.4. Mng ng (mng con tr)- Khai bo

kiu_d_liu* tn_bin = new kiu_d_liu[spt];- Hu mng ng:

delete [] tn_bin;- u im: s dng c mng vi s phn t rt ln- V d:

#define MAX 100000int * a = new int [MAX];for (int i = 0 ; i< MAX ; i++)

a[i] = i;delete[] a;


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9.5. Chui con tr- Khai bo- char* tn_chui = new char[chiu_di_ti_a_ca_chui];- Hu chi:- delete[] chui;

- Khi ta c th s dng cc lnh v chui p dng cho chui con trmt cch bnh thng

9.6. Con tr kiu cu trc:V d:

struct PHANSO{

int tu;int mau;

};int main(){

PHANSO *ps; //con tr lu a ch ca bin kiu cu trcps = new PHANSO;

//truy cp n trng ca cu trc bng du chm (.)*ps . tu = 1;*ps . mau = 2;cout


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9.7. Mi quan h gia mng v con tr:Tn mng l mt hng a ch

int a[10];a tng ng vi &a[0] (a ch ca phn t a[0])a + i tng ng vi &a[i] (a ch ca phn t a[i])

*(a+i) tng ng vi a[i]

V vy ta c th tr con tr n bin mng nh sau:int *p;int a;

p = a;p tng ng vi &a[0] (a ch ca phn t a[0])p + i tng ng vi &a[i] (a ch ca phn t a[i])*(p+i) tng ng vi a[i]

hoc: int *p;int a;

p = &a[k];p tng ng vi &a[k] (a ch ca phn t a[k])p + i tng ng vi &a[k + i] (a ch ca phn t a[k+i])*(p+i) tng ng vi a[k+i]

9.8. Mt s v d n gin:

#include #include using namespace std;int main(){

int * p;int a = 1;

p = & a;cout


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cout


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Chng 10: Th vin STL(Standard Template Library)

10.1. iostream: #include cc lnh lin quan n vic xut nhp

Lnh ngha V dcout xut chun cout


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10.4. i tng string: #include + khai bo i tng string

string tn_i_tng_string;+ Nhp v xut

string s; //Khai bo mt i tng stringcin>>s; //Nhp vo chui khng c khong trnggetline(cin, s); //Nhp vo mt chui c khong trng

+ Cc phng thc ca i tng stringPhng thc ngha V d

size() - Ly chiu di chui string s = hello;cout


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-1: s1 nh hn s2find(char kt , int chis_bdu)find(string chui, intchis_bdu)

Tm k t (hoc chui) trongdy bt u t ch_s_bduca chui.- nu tm thy s ch ra v tr

ca k t (chui) trong chui- nu k tm thy s tr v -1

string s = hello;

int i = s.find( e ); //i=1

int j = s.find( t ); //i=-1

Ton t + cng 2 chui string s1 =Hellostring s2 = World

string s = s1 + s1;//s=Hello World

Ton t [] Truy cp n phn t cachui

cout


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getch();return 0;

}

getch();return 0;

}

Cc phng thc c bn ca vector

Phng thc ngha V dpush_back Thm phn t vo cui

vector

size() - kch thc (s lng phn

t) ca vector

vector vec;

vec.push_back(2);vec.push_back(1);vec.push_back(3);

//Khi //vec[0]=2,vec[1]=2,vec[3]=3cout


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10.6. fstream: #include a. Mc ch:

+ Qun l vic nhp d liu t File (i tngifstream)+ Qun l vic xut d liu vo File (i tngoifstream)

b. Nhp d liu t File:Nhp d liu t bn phm Nhp d liu t file+ Kh qun l d liu nhp + D liu nm trong file, nn d qun

l+ Mi ln chy chng trnh l phinhp d liu li

+ Mi ln chy chng trnh ta khngcn nhp d liu li

+ Khng cn file lu tr d liu + Phi to file lu tr d liu trc khichy chng trnh (thng l *.txt)

V dvit chng trnh nhp vo ba s nguyn a, b, cNhp d liu t bn phm Nhp d liu t file#include #include

using namespace std;

int main()

{ int a, b, c;

cin>>a;cin>>b>>c;

getch();return 0;

}

#include #include #include


int main()

{ int a, b, c;

ifstream ifile;//To i tng ifstreamifile.open(data.txt); //M file data.txt

ifile>>a;ifile>>b>>c;

//ng fileifile.close();

getch();return 0;

}


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Ch :Ngi ta thng dng phng thc eof() ca ifstream kim tra l c

ht file cha (thng dng vic nhp d liu cho mng t file)

ifstream ifile;//To i tng ifstream

ifile.open(data.txt); //M file data.txt

int n = 0;

//Trong khi cha c ht filewhile (!ifile.eof()){

ifile>>a[n++];}

//ng fileifile.close();

V tr cui file:ifile.eof() == true


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c. Xut d liu vo File:

Xut d liu ra mn hnh Xut d liu ra file+ Kh qun l d liu xut + D liu c xut ra file, nn d

qun l

V d vit chng trnh nhp vo ba s nguyn a, b, cNhp d liu t bn phm Nhp d liu t file

#include #include


int main(){int a, b, c;a= 1;

b= 2;c= 3;

cout

Lap trinh C++ - FINAL

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