C program to find sum and difference of two numbers

In C programming, finding the sum and difference of two numbers is a fundamental operation. This program demonstrates how to perform arithmetic operations on different data types and handle the output formatting correctly based on the operands' types.

Syntax

// For integer arithmetic
int result = num1 + num2;
int result = num1 - num2;

// For floating-point arithmetic  
float result = num1 + num2;
float result = num1 - num2;

Example 1: Sum and Difference of Integer Numbers

This example shows basic arithmetic operations on integer values −

#include <stdio.h>

int main() {
    int a = 15, b = 8;
    
    printf("First number: %d
", a);
    printf("Second number: %d
", b);
    printf("Sum: %d + %d = %d
", a, b, a + b);
    printf("Difference: %d - %d = %d
", a, b, a - b);
    
    return 0;
}

First number: 15
Second number: 8
Sum: 15 + 8 = 23
Difference: 15 - 8 = 7

Example 2: Sum and Difference of Floating-Point Numbers

This example demonstrates arithmetic operations on floating-point values −

#include <stdio.h>

int main() {
    float c = 6.32, d = 8.64;
    
    printf("First number: %.2f
", c);
    printf("Second number: %.2f
", d);
    printf("Sum: %.2f + %.2f = %.2f
", c, d, c + d);
    printf("Difference: %.2f - %.2f = %.2f
", d, c, d - c);
    
    return 0;
}

First number: 6.32
Second number: 8.64
Sum: 6.32 + 8.64 = 14.96
Difference: 8.64 - 6.32 = 2.32

Example 3: Mixed Data Type Operations

This example shows arithmetic operations between integer and floating-point numbers −

#include <stdio.h>

int main() {
    int a = 5, b = 58;
    float c = 6.32, d = 8.64;
    
    printf("Integer operations:
");
    printf("a + b = %d
", a + b);
    printf("b - a = %d
", b - a);
    
    printf("\nFloat operations:
");
    printf("c + d = %.6f
", c + d);
    printf("d - c = %.6f
", d - c);
    
    printf("\nMixed operations:
");
    printf("a + c = %.6f
", a + c);
    printf("b - d = %.6f
", b - d);
    
    return 0;
}

Integer operations:
a + b = 63
b - a = 53

Float operations:
c + d = 14.960001
d - c = 2.320000

Mixed operations:
a + c = 11.320000
b - d = 49.360001

Key Points

• When adding integers, use %d format specifier for output.
• When adding floats, use %f or %.nf (where n is decimal places) format specifier.
• Mixed operations (int + float) automatically promote the integer to float, requiring %f for output.
• Floating-point arithmetic may introduce small precision errors due to binary representation.

Conclusion

Arithmetic operations in C are straightforward, but proper format specifiers must be used based on data types. Mixed operations automatically promote integers to floating-point for accurate results.