C program to check whether a given number is a power of 2 using bitwise operations

⚡ Check If a Number Is a Power of 2

#include<stdio.h>

int power(int num)
{
    if(num > 0 && (num & (num - 1)) == 0)
    {
        return 1;
    }
    else
    {
        return 0;
    }
}

int main()
{
    int num;
    scanf("%d", &num);
    
    if(power(num))
    {
        printf("%d is a power of 2\n", num);
    }
    else
    {
        printf("%d is not a power of 2\n", num);
    }
}
  

📘 Explanation:

✅ The condition (num & (num - 1)) == 0 is true only if there is only one set bit in num.
✅ This logic efficiently checks whether a number is a power of 2.
✅ It excludes 0 and negative numbers.

🧪 Sample Output:

Input:
8
Output:
8 is a power of 2
    

🏷️ Keywords:

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