Parse Comma-Separated Integers into an Array

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

int is_digit(char c){
    return (c >= '0' && c <= '9');
}

void parse_csv_to_array(const char *str, uint8_t *arr, uint8_t *count) {
uint8_t i = 0;              // Index for iterating through the string
    uint16_t current_num = 0;   // Accumulator for building the number
    uint8_t has_number = 0;     // Flag to track if we are currently parsing a number
    
    *count = 0;                 // Ensure the array index starts at 0

    while(str[i] != '\0'){
        if(is_digit(str[i])){
            // Multiply by 10 to shift the digit left (handles multi-digit numbers like 12)
            current_num = (current_num * 10) + (str[i] - '0');
            has_number = 1;
        } 
        else if (str[i] == ',') {
            // When we hit a comma, save the built number to the array
            if (has_number) {
                arr[*count] = (uint8_t)current_num;
                (*count)++;        // Move to the next slot in the array
                current_num = 0;   // Reset the accumulator for the next number
                has_number = 0;    // Reset the flag
            }
        }
        i++;
    }
    
    // Catch the final number in the string (since there is no comma at the very end)
    if (has_number) {
        arr[*count] = (uint8_t)current_num;
        (*count)++;
    }
}

int main() {
    char str[101];
    fgets(str, sizeof(str), stdin);

    // Remove newline
    uint8_t i = 0;
    while (str[i]) {
        if (str[i] == '\n') {
            str[i] = '\0';
            break;
        }
        i++;
    }

    uint8_t arr[20];
    uint8_t count = 0;

    parse_csv_to_array(str, arr, &count);

    for (uint8_t i = 0; i < count; i++) {
        printf("%u", arr[i]);
        if(i < count - 1){
            printf(" ");
        }
    }
    return 0;
}