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
    if (reg == 0) return 0;
    uint8_t idx = 16;
    uint16_t mask = (1 << 15);
    while(!(mask & (reg << (16-idx)))){
        idx--;
    }

    return (1 << (idx-1));
}

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

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

Solving Approach