#include <iostream>

#include "charUtils.h"

using namespace std;

int stringToNumber(char chars[]) {

int result = 0;

if (chars == NULL || chars[0] == '\n' || chars[0] == '-') {

cout << "input invalid, Support only number";

return 0;

}

int digit = chars[0] - '0';

int i = 1;

while (chars[i] != '\0') {

digit = (chars[i] - '0') + (digit * 10);

cout << "digit " << digit << '\n';

i++;

if(i > 9) {

throw invalid_argument("input argument length big than 9");

}

}

return digit;

}