Programmin in C

7/27/2019 Programmin in C

1/19

PROGRAMING IN C

Tutorial


2/19

A Simple C program

#include

int main( ) {

printf("hello, world");

return 0;

}


3/19

Variables; Types and Type Declarations

#include

int main( ) {

int a, b, c, sum;

a = 1; b = 2; c = 3;

sum = a + b + c;

printf("sum is %d", sum);

return 0;

}


4/19

Variables; Types and Type

Declarations


5/19

Simple I/O getchar(), putchar(), printf ()

int main( ) {char c;

c = getchar( );

putchar(c);

getchar();

}

printf("hello, world");

printf("sum is %d", sum);


6/19

Simple I/O getchar(), putchar(), printf()

n = 511;

printf("What is the value of %d in octal?", n);

printf("%s! %d decimal is %o octal\n", "Right", n, n);

What is the value of 511 in octal? Right! 511 decimal is 777 octal


7/19

If - relational operators and compound

statements

if(expression) statement

== equal to!= not equal to

> greater than

< less than

>= greater than or equal to


8/19

If - relational operators and compound

statements

C guarantees that `&&' and `||' are evaluated left to right --we shall soon see cases where this matters.

if( c==' ' || c=='\t' || c=='\n' ) ...

Grouped together by {}

if (a < b) {

t = a;

a = b;

b = t;

}


9/19

Else Clause; Conditional Expressions

if (expression) statement1 else statement2

if (a < b)

x = a;

elsex = b;

expr1 ? expr2 : expr3

a


10/19

a common programming structure

if(...)

{...}

else if(...){...}

else if(...)

{...} else {...}


11/19

The Switch Statement ; Break ;

Continueswitch( c ) {

case 'a':

aflag++;

break;

case 'b':

bflag++;break;

case 'c':

cflag++;

break;

default:printf("%c?\n", c);

break;

}


12/19

While Statement; Assignment within

an Expression; Null Statement

while (expression) statement

int main( ) {char c;

while( (c=getchar( )) != '\0' )

putchar(c);

return 0;

}


13/19

for Statement

for( initialization; expression; increment)

statement

initialization;

while( expression ) {

statement

increment;

}


14/19

for Statement

sum = 0;

for( i=0; i


15/19

Arithmetic

x = a%b;

c = c + 'A' - 'a';

main( ) {

char c;


if( 'A'


16/19

Increment and Decrement Operators

int k=5;

x = ++k;

x = k++;

main( ) {

int c,n;

n = 0;


if( c == '\n' )

++n;printf("%d lines\n", n);

}


17/19

Arrays

int x[10];

x[0], x[1], x[2], ..., x[9]

main( ) {

int n, c;

char line[100];n = 0;

while( (c=getchar( )) != '\n' ) {

if( n < 100 )

line[n] = c;

n++;}

printf("length = %d\n", n);

}


18/19

Character Arrays; Strings

We can copy a character array s into another t like this:

main( ) {

int n;

char line[100];n = 0;

while( (line[n++]=getchar( )) != '\n' );

line[n] = '\0';

printf("%d:\t%s", n, line);

}


19/19

Example to count letters, digits and

others in a filemain( ) {

int let, dig, other, c;

let = dig = other = 0;


if( ('A'

Programmin in C

Documents

Transcript of Programmin in C