70分求助！！！大佬们帮忙看看

#include<iostream>
#include<cstring>
#include<stdio.h>

using namespace std;

void judge(char a[14])
{
    int sum = 0, n, k = 1;
    char m;
    for (int i = 0; i < 11; i++)
    {
        if (a[i] != '-')
        {       
            sum += (a[i] - '0') * k;
            k++;
        }
    }
    n = sum % 11;
    m = n + '0';
    if (m == a[12]) cout << "Right";
    else if (n == 10 && a[12] == 'X') cout << "Right";
    else
    {
        cout << a;
    }
}

int main()
{
    char ISBN[14];
    cin >> ISBN; 
    judge(ISBN);
}