Clear Specific Bits in a 32-bit Register

Code

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

uint32_t clear_bits(uint32_t reg, uint8_t pos, uint8_t len) 
{
    uint32_t shift_num = pow(2 , len) - 1;
    
    shift_num = shift_num << pos;
    
    return reg & ~(shift_num);
}

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;
}

Solving Approach