求助，全WA，但下载测试样例本地调试后输出一样

#include <iostream>
#include <string>
using namespace std;
int main()
{
	ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);
	int q;
	cin >> q;
	string s;
	// 读取换行符
	cin.get();
	getline(cin,s);
	for (int i = 0; i < q; i++)
	{
		int n;
		cin >> n;
		string s2;
		switch(n)
		{
			case 1:
				{
					cin >> s2;
					s+=s2;
					cout << s << endl;
					break;
				}
			case 2:
				{
					int n1,n2;
					cin >> n1 >> n2;
					s2="";
					for (int i = n1; i < n1+n2; i++)
					{
						s2+=s[i];
					}
					s = s2;
					cout << s << endl;
					break;
				}
			case 3:
				{
					int a;
					cin >> a;
					cin >> s2;
					s.insert(a,s2);
					cout << s << endl;
					break;
				}
			case 4:
				{
					cin >> s2;
					if (s.find(s2) != string::npos)
						cout << s.find(s2) << endl;
					else
						cout << -1 << endl;
					break;
				}
		}
	}
	return 0;
}