Convert Integer to Hex String Without sprintf or itoa functions

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

void print_hex(uint16_t num) {
    // Your logic here
    char buffer[5] = {0};
    uint16_t remainder;
    buffer[4] = '\0';

    int i = 3;
    if(num == 0)
    {
        printf("0");
        return;
    } 
    while(num > 0 && i >= 0)
    {   
        remainder = num & 0x0F; //num % 16
        buffer[i--] = remainder < 10 ? remainder + '0' :remainder -10 + 'A';
        num >>= 4;  //num /=16
    }

    printf("%s",&buffer[i+1]);
}

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