Keep Only the Highest Set Bit

Code

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

// Complete the function
uint16_t highest_set_bit(uint16_t reg) {
    uint8_t pos;
    uint8_t max = 0;
    for (pos = 0; pos<16; pos+=1)
    {
        if (reg & (1 << pos))
        {
            max = pos;
        }
    }

    reg &= ~((1<<max)-1 << 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