#include <iostream>
#include <string>
using namespace std;
int main(int argc, char* argv[])
{
	int N;
	string s,t;
	cin>>N;
	cin>>s;
	cin>>t;
	int i=0;
	int j=0;
	for (;;){
		if (s[i]==t[j]){
			j++;
		}
		i++;
		if (i==N){
			cout<<2*N-j<<endl;
			break;
		}
	}
	return 0;
}
### Prompt

Your challenge is to write a Cpp solution to the following problem:

Snuke is interested in strings that satisfy the following conditions:

* The length of the string is at least N.
* The first N characters equal to the string s.
* The last N characters equal to the string t.



Find the length of the shortest string that satisfies the conditions.

Constraints

* 1≤N≤100
* The lengths of s and t are both N.
* s and t consist of lowercase English letters.

Input

The input is given from Standard Input in the following format:


N
s
t


Output

Print the length of the shortest string that satisfies the conditions.

Examples

Input

3
abc
cde


Output

5


Input

1
a
z


Output

2


Input

4
expr
expr


Output

4

### Response

```cpp
#include <iostream>
#include <string>
using namespace std;
int main(int argc, char* argv[])
{
	int N;
	string s,t;
	cin>>N;
	cin>>s;
	cin>>t;
	int i=0;
	int j=0;
	for (;;){
		if (s[i]==t[j]){
			j++;
		}
		i++;
		if (i==N){
			cout<<2*N-j<<endl;
			break;
		}
	}
	return 0;
}
```