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) {
    int val;
    uint16_t digit;
    for(int i=0;str[i];i++){
        if(str[i]>='A'&&str[i]<='Z'){
    val=(str[i]>='A')?(str[i]-'A'+10):(str[i]-'0');
    digit=(digit<<4)|val;}
    else{
         val=(str[i]>='a')?(str[i]-'a'+10):(str[i]-'0');
    digit=(digit<<4)|val;
    }}
    return digit;
}

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

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

Solving Approach