Modify Bytes in a 32-bit Value Using Union

Code

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

typedef union {
    uint32_t value;
    uint8_t bytes[4];
} Register;

// Write logic here using union to modify byte[1] and byte[2]
void modify_and_print(uint32_t input, uint8_t b1, uint8_t b2) {
    // Your logic here
    Register r;
    r.value = input;
    r.bytes[1] = b1;
    r.bytes[2] = b2;
    printf("%u", (uint32_t) r.value);
}

int main() {
    uint32_t num;
    uint8_t b1, b2;
    scanf("%u %hhu %hhu", &num, &b1, &b2);
    modify_and_print(num, b1, b2);
    return 0;
}

Solving Approach

transfer the value to the register value, change the bytes 1 & 2, 

then print the value of the register (unsigned 32bit int)