样例2，“Wrong answer Too long on line 3”

评测记录

代码：

#include <iostream>
#include <algorithm>
#include <cstdio>
#include <cmath>
#include <string>
using namespace std;

int n;
int op;

int l, r;

string s;
string a;
string b;

int main()
{
	scanf("%d", &n);
	cin >> s;
	for (int i = 1;i <= n;i++)
	{
		scanf(" %d", &op);
		if (op == 1)
		{
			cin >> a;
			s += a;
			cout << s;
			printf("\n");
		}
		else if (op == 2)
		{
			cin>>l>>r;
			b = s.substr(l,r);
			s = b;
			cout << s;
			printf("\n");
		}
		else if (op == 3)
		{
			scanf("%d", &l);
			cin >> a;
			s.insert(l,a);
			cout << s;
			printf("\n");
		}
		else if (op == 4)
		{
			cin >> a;
			if (s.size() > s.find(a))
				printf("%d\n", s.find(a));
			else
				printf("-1");
		}
	}
    return 0;
}