The following program shows how to add two integer numbers in C language:

#include <stdio.h>
#include <conio.h>

void main ()
int a,b,c;
printf("Program to add two numbers\n");
printf("Enter two numbers of integer type:\n");
printf ("Enter the first number:");
scanf ("%d",&a);
printf ("\nEnter second number:");
scanf ("%d",&b);
printf ("\nSum of two numbers = %d",c);
When you run the above program, it prompts you to enter two integer data type numbers. Once you entered those two numbers, the program prints the sum of those two numbers.