Extract and Modify Field in a 32-bit Register

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

uint32_t update_register(uint32_t reg) {
    // Your logic here
    uint32_t mask = ((1<<5) - 1)<<10;
    uint32_t ext = (reg & mask) >> 10;
    if(ext < 31)    ext += 1;
    reg = (reg & ~mask) | (ext << 10);

    return reg;
}

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