20. Clear Specific Bits in a 32-bit Register

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

uint32_t clear_bits(uint32_t reg, uint8_t pos, uint8_t len) {
    // Your code here
    if(!(pos > 31 || len > 32 || pos + len > 32 || len == 0)){
        uint32_t mask = ((1 << len) - 1) << pos;
        return reg & ~mask;
    }
    else {
        return (uint32_t)-1;
    }

}

int main() {
    uint32_t reg;
    uint8_t pos, len;
    scanf("%u %hhu %hhu", &reg, &pos, &len);
    printf("%u", clear_bits(reg, pos, len));
    return 0;
}