Replace Bit Field in a 32-bit Register

Code

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

uint32_t replace_field(uint32_t reg, uint32_t val, uint8_t pos, uint8_t len) {
    // Your code here
   // reg &= ~(((1 << len) - 1) << pos);

   // reg |= (val & ((1 << len) - 1)) << pos;
     uint32_t clear_mask = ~(((1U << len) - 1) << pos);
     uint32_t set_mask = (val & ((1U << len) - 1)) << pos;
     reg &= clear_mask;
      reg |= set_mask;

    return reg;
}

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

Solving Approach