Convert Hexadecimal String to Integer Without strtol or sscanf functions

Code

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

uint16_t hex_to_uint(const char *str) {
    // Your logic here
    uint16_t result = 0;
    while(*str != '\0')
    {
        if(*str >= '0' && *str <= '9')
        {
            result = result * 16 + (*str - '0');
        }
        else if(*str >= 'A' && *str <= 'F')
        {
            result = result * 16 + ((*str - 'A') + 10);
        }
        else
        {
            result = result * 16 + ((*str - 'a') + 10);
        }
        str++;
    }
    return result;
}

int main() {
    char hex[10];
    scanf("%s", hex);

    printf("%u", hex_to_uint(hex));
    return 0;
}

Solving Approach