Is the juge bad??

here is my program:
someone who accepted can check it??
Thanks for your kindness!

#include <iostream>
using namespace std;

int N;

int main()
{
    int r1, r2, wait = -1;
    int nines = 0;

    cin >> N;
    for (int i = 0; i < N; ++i)
    {
        cin >> r1 >> r2;
        if (r1 + r2 != 9)
        {
            if (r1 + r2 > 9) {
                cout << wait + 1;
                while (nines > 0) {
                    cout << 0;
                    --nines;
                }
            }
            else {
                if (wait != -1)
                    cout << wait;
                while (nines > 0) {
                    cout << 9;
                    --nines;
                }
            }
            wait = (r1 + r2) % 10;
        }
        else {
            nines++;
        }
    }
    //
    if (wait != -1)
        cout << wait;

    while (nines > 0) {
        cout << 9;
        --nines;
    }
    cout << endl;
    //
    return 0;
}