Study of arithmetic operation on integers.
  #include <stdio.h>

int main(void)
{
/* variable declaration statements */
int num1, num2, res;

/* Assign values to variables num1 and num2 */
num1 = 100;
num2 = 20;

/* Perform various arithmetic operations */
res = num1 + num2;
printf("\n %d + %d = %d", num1, num2, res);

return 0;
}