120. Convert Integer to Hex String Without sprintf or itoa functions

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

void print_hex(uint16_t num) {
    if(!num){ printf("0");
    return; }
    for (int i = 12; i >= 0; i -= 4) {
    int a = (num >> i) & 0xF;
    if (a==0) continue;
    else if (a < 10)
        printf("%d", a);
    else
        printf("%c", 'A' + (a - 10));
}
}

int main() {
    uint16_t num;
    scanf("%hu", &num);
    print_hex(num);
    return 0;
}