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
   uint16_t value = 0;
    char c;

    for (int i = 0; (c = str[i]) != '\0'; i++) {
        uint8_t digit;

        if (c >= '0' && c <= '9')
            digit = c - '0';
        else if (c >= 'A' && c <= 'F')
            digit = c - 'A' + 10;
        else if (c >= 'a' && c <= 'f')
            digit = c - 'a' + 10;
        else
            break;  // stop on invalid character

        value = (value << 4) | digit;
    }

    return value;
}

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

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

Solving Approach