SDNU 1120.ISBN号码

#include<bits/stdc++.h>
using namespace std;
#define ll long long

char c[18], s;

int main()
{
    scanf("%s", c);
    int ii = 1, sign = 0, len = strlen(c), sum = 0;
    for(int i = 0; i<len; i++)
    {
        if(sign<9 && c[i] != ‘-‘)
        {
            sum += ii*((int)c[i]-48);
            ii++;
            sign++;
        }
    }
    sum %= 11;
    if(sum == 10)s = ‘X‘;
    else s = sum+48;
    if(s == c[len-1])printf("Right\n");
    else
    {
        for(int i = 0; i<len-1; i++)
            printf("%c", c[i]);
        printf("%c\n", s);
    }
    return 0;
}