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
    // 4 = 100 
    // 3 = 011 // 10
    // & = 000
    // 2 to the power of something

    if( reg & (reg - 1) == 0 ) return reg;
    int len = 15; 
    while(len)
    {
        if( ((reg >> len)&1)&1)
        {
            len--; 
            while(len >= 0){
                reg &= ~(1 << len); 
                len--; 
            }
            return reg; 
        }
        len--; 
    }
    return 0; 
}

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

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

Solving Approach