本地数据全过了，但上传后都WA了，求助sos

#include<iostream>
#include<sstream>
#include<string>

using namespace std;

int main()
{
    int state=0;
    int n;
    string s,t;
    cin >> n;
    cin.ignore();
    while(n--)
    {
        getline(cin, s);
        stringstream ss(s),sss;
        int x, y;
        if (s[0]>='a'&&s[0]<='c')
        {
            ss >> t;                
            switch (s[0])
            {
            case 'a':
                state = 1; break;
            case 'b':
                state = 2; break;
            case 'c':
                state = 3; break;
            default:
                break;
            }
        }

        if (state == 1)
        {
            ss >> x, ss >> y;
            cout << x << '+' << y << '=' << x + y << endl;
            sss << x << y << x + y;
            sss >> t;
            cout << t.size() + 2;
            if(n!=0)    cout<<endl;
        }
        else if (state == 2)
        {
            ss >> x, ss >> y;
            cout << x << '-' << y << '=' << x - y << endl;
            sss << x << y << x - y;
            sss >> t;
            cout << t.size() + 2;
            if (n != 0) cout << endl;
        }
        else if (state == 3)
        {
            ss >> x, ss >> y;
            cout << x << '*' << y << '=' << x * y << endl;
            sss << x << y << x * y;
            sss >> t;
            cout << t.size() + 2;
            if (n != 0) cout << endl;
        }
    }
}