Set Specific Bits in a 32-bit Register

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

uint32_t set_bits(uint32_t reg, uint8_t pos, uint8_t len) {
    // Your code here
    
    if((pos >= 0) && (pos < 32))
    {
        if((len >= 0) && (len < 32))
        {
            uint32_t new_reg = (1<<len) - 1;
            return reg |= new_reg<<pos;
        }
        else
        {
            return 0;
        }
    }
    else
    {
        return 0;
    }
    return 0;
}

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