26. 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
    uint8_t len = 5;
    uint8_t pos = 10;
    uint32_t mask = 0x1F;

    uint32_t extractbit = 0;
    extractbit = (reg>>pos) & mask;
    if( extractbit < 31 )
    {
        extractbit += 1;
    }

    mask = ((1<<len)-1)<<pos;
    reg &= ~mask;
    reg |= (extractbit & (1<<len)-1)<<pos;
    return reg;
}

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