Convert Hexadecimal String to Integer Without strtol or sscanf functions

Code

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

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

        str++;
    }
    return result;
}

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

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

Solving Approach

int result=0;
    while(*str)
    {
        result *=16;
        if(*str>='0' && *str<='9')
        {
            result+=*str-'0';
        }
        else if(*str>='A' && *str<='Z')
        result+=*str-'A'+10;
        else if(*str>='a' && *str<='z')
        result+=*str-'a'+10;

        str++;
    }
    return result;