Swap Two Values without Third Variable In C

 

 Swap Two Values without Third Variable In C 

#include <stdio.h>

int main() {

    int a, b ;

    // Ask user to enter two numbers

    printf("Enter Value of a & b: ");

    scanf("%d%d", &a,&b);

    // Add the two numbers

a = a + b ;

    b = a - b ;

    a = a - b ;

    // Display the result

    printf("value after Swap of : a=%d and b=%d",a,b);

    return 0;

}

Detailed Explanation:

1. Initial Input:

   • The program prompts the user to enter two integer values for a and b.
   • Example: Suppose the user enters a = 5 and b = 3.

2. Step-by-Step Execution:

   • Step 1: a = a + b;
     • This calculates the sum of a and b and stores it in a.
     • For a = 5 and b = 3, it becomes a = 5 + 3 = 8.
   • Step 2: b = a - b;
     • This calculates the original value of a by subtracting the current value of b from the current value of a.
     • For a = 8 and b = 3, it becomes b = 8 - 3 = 5.
   • Step 3: a = a - b;
     • This calculates the original value of b by subtracting the current value of b (which is now the original value of a) from the current value of a.
     • For a = 8 and b = 5, it becomes a = 8 - 5 = 3.

3. Final Values:

   • After these operations, the values of a and b are swapped.
   • a is now 3 and b is now 5.

4. Output:

   • The program prints the swapped values.
   • The output will be: value after Swap of : a=3 and b=5.

Example Run:

Enter Value of a & b: 5 3
value after Swap of : a=3 and b=5

This method of swapping values works by manipulating the sums and differences of the variables, effectively exchanging their values without the need for a temporary storage variable.