#include<iostream>
#include<cstdio>
#include<map>
#include<string>
using namespace std;
map<string,bool>S;
char com[7];
char  str[13];
int n;

int main(){
	scanf("%d",&n);
	for(int j=0;j<n;j++){
	scanf("%s %s",com,str);
	if(com[0]=='i'){
		S[string(str)]=true;
		}
		else if(S[string(str)]==true){
			cout<<"yes"<<endl;
		}
	    else if(S[string(str)]!=true){
	         cout<<"no"<<endl;
			}
	}
	return 0;
	}
### Prompt

Please formulate a Cpp solution to the following problem:

Your task is to write a program of a simple dictionary which implements the following instructions:

* insert str: insert a string str in to the dictionary
* find str: if the distionary contains str, then print 'yes', otherwise print 'no'

Notes

Template in C

Constraints

* A string consists of 'A', 'C', 'G', or 'T'
* 1 ≤ length of a string ≤ 12
* n ≤ 1000000

Input

In the first line n, the number of instructions is given. In the following n lines, n instructions are given in the above mentioned format.

Output

Print yes or no for each find instruction in a line.

Examples

Input

5
insert A
insert T
insert C
find G
find A


Output

no
yes


Input

13
insert AAA
insert AAC
insert AGA
insert AGG
insert TTT
find AAA
find CCC
find CCC
insert CCC
find CCC
insert T
find TTT
find T


Output

yes
no
no
yes
yes
yes

### Response

```cpp
#include<iostream>
#include<cstdio>
#include<map>
#include<string>
using namespace std;
map<string,bool>S;
char com[7];
char  str[13];
int n;

int main(){
	scanf("%d",&n);
	for(int j=0;j<n;j++){
	scanf("%s %s",com,str);
	if(com[0]=='i'){
		S[string(str)]=true;
		}
		else if(S[string(str)]==true){
			cout<<"yes"<<endl;
		}
	    else if(S[string(str)]!=true){
	         cout<<"no"<<endl;
			}
	}
	return 0;
	}
```