c program for programmers - 2

using math .h 

#include "stdio.h"

#include "math.h"

void main ( )

{

int a,b,c;

a= 10;

b=20;

c=a+b;

printf("sum=%d\n",c);
getchar( );

}
output
sum=30

note : 

1. you  can  change  the  operator  symbol  like + : add , - :subtract ,  / : divide ,                                    * :  multiplication ; ^:exportation.
2. if you want to write the numbers in decimals write for int write float in printf for %d write %f