C PROGRAM • INPUT, OUTPUT & OPERATORS

Add Two Integers

Read two integers, add them and inspect how the result variable receives the calculated value.

Beginnerscanf()AdditionVariables

PROBLEM UNDERSTANDING

Input and expected output

Sample input

12 8

Sample output

Enter two integers: 12 8
Sum = 20

C PROGRAM

Complete program

#include <stdio.h>

int main(void)
{
    int first, second, sum;
    printf("Enter two integers: " );
    scanf("%d %d", &first, &second);
    sum = first + second;
    printf("Sum = %d\n", sum);
    return 0;
}

First integerSecond integer

CURRENT STEP

Select Start to trace this program.

VARIABLES

Scope	Name	Value
Not started

CALL STACK

main()

PROGRAM OUTPUT

Waiting to run…

0%Step 0 of 0

PROGRAM EXPLANATION

Algorithm and explanation

Read two integers.
Add the values and store the result in sum.
Print sum.

scanf() stores the entered integers in first and second. The + operator produces a new value, which is assigned to sum before printf() displays it.

EFFICIENCY

Time and space complexity

Time complexity

O(1)

Auxiliary space

O(1)

DEBUGGING CHECKLIST

Common mistakes

Check this

Forgetting & before variables in scanf().

Check this

Using the wrong format specifier for an integer.