Extract and Modify Field in a 32-bit Register

Code

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

uint32_t update_register(uint32_t reg) {
    uint8_t pos = 10;
    uint8_t len = 5;
    uint32_t mask = ((1<<len)-1);
    uint32_t temp = reg &~(mask << pos);
    mask = (reg & (mask << pos)) >> pos;
    if(mask < 31)
    {
        mask+=1;
    }
    reg = temp|(mask<<pos);

    return reg;
}

int main() {
    uint32_t reg;
    scanf("%u", &reg);
    uint32_t updated = update_register(reg);
    printf("%u", updated);
    return 0;
}

Solving Approach