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 !='\0'){
        result<<=4;
        if(*str>='0'&&*str<='9'){
            result+=*str-'0';
            str++;
        }
        else if(*str>='A'&&*str<='F'){
            result+= *str-'A'+10;
            str++;
        }
        else if(*str >='a'&& *str <='f'){
            result += *str-'a'+10;str++;
        }
        else 
        str++;
    }
    return result;
}

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

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

Solving Approach