Set Specific Bits in a 32-bit Register

Code

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

uint32_t set_bits(uint32_t reg, uint8_t pos, uint8_t len) {
    // Your code here
    int num = 1;
    while(len--){
        num = num * 2;
    }

    return (reg | ((num-1) << pos));
}

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;
}

Solving Approach

If 5 bits are to be set starting from position 0, it means register value should be applied bit wise and operation with 11111, i.e, (2^5 - 1).