Problem:
Score : 200 points

Problem Statement

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.

Sample Input 1

3
abc
cde

Sample Output 1

5

The shortest string is abcde.

Sample Input 2

1
a
z

Sample Output 2

2

The shortest string is az.

Sample Input 3

4
expr
expr

Sample Output 3

4

The shortest string is expr.

Solution in C++14 (GCC 5.4.1) (judge verdict: Accepted)

#include<iostream>
#include<vector>
#include<algorithm>
#include<math.h>
#include<queue>
#include<stack>
#include<string>

using namespace std;
const int INF = 1<<30;
typedef long long int ll;

int main(){
	int n;cin>>n;
	string s, t;cin>>s>>t;
	int ans=int(s.size()+t.size());
	for(int i=0;i<n;i++){
		string tmp = s.substr(i, n-i);
		bool match=true;
		for(int j=0;j<n-i;j++){
			if(t[j]!=tmp[j]){match=false;break;}
		}
		if(match){ans=int(t.size())+i;break;}
	}
	cout<<ans<<endl;
}