Keep Only the Highest Set Bit

Code

#include <stdio.h>
#include <stdint.h>

// Complete the function
uint16_t highest_set_bit(uint16_t reg) {
    // Your logic here
    int index = 0;
    for (int i = 15; i>= 0; i--){
       if ((reg >> i) & 1){
        index = i;
        break;
       }
    }
    if (index !=0) {
    reg &= (~0 << index);
    reg |= (1<<index);
    }
    else {
        return 0;
    }
    return reg;
}

int main() {
    uint16_t reg;
    scanf("%hu", &reg);

    uint16_t result = highest_set_bit(reg);
    printf("%hu", result);
    return 0;
}

Solving Approach