- C program to count trailing zeros in binary representation of a number using bitwise operator

**Algorithm to count trailing zero bits in a number.**

- Check whether least significant bit of a number(N) is 0 or not by doing bitwise And(&) with 1. if (N & 1) == 0, that means last bit is 0 otherwise 1.
- If last bit is 0, then increment a counter and right shift N by one bit position.
- Repeat above steps until (N & 1) == 1 or N ==0.

## C Program to count trailing zeros of a number using bitwise operator

#include<stdio.h> #include<stdlib.h> int main() { int num, count = 0; char str[100]; printf("Enter an integer\n"); scanf("%d", &num); /* Convert integer to a binary number using atoi and store it in a string */ itoa(num, str, 2); printf("Binary Number : %s\n", str); /* count number of trailing zero's in binary representation of num */ while (num != 0) { if (num & 1 == 1) { break; } else { count++; num = num >> 1; } } printf("Number of Trailing Zeros = %d", count); return 0; }Output

Enter an integer 60 Binary Number : 111100 Number of Trailing Zeros = 2

Enter an integer 15 Binary Number : 1111 Number of Trailing Zeros = 0