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 <bits/stdc++.h>
using namespace std;
#define fi first
#define endl "\n"
#define se second
#define ll long long
//priority_queue<int, vector<int>, greater<int> > pq;
#define _CRT_SECURE_NO_DEPRECATE
const int N = 105;
#define rep(i, begin, end) for (__typeof(end) i = (begin) - ((begin) > (end)); i != (end) - ((begin) > (end)); i += 1 - 2 * ((begin) > (end)))
const ll mod =  1e9+7;

int main()
{
    ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
int n;
cin>>n;
string s,t;
cin>>s>>t;
int ans=0;
rep(i,0,n)
{
	string ss,tt;
	ss=s.substr(i,n-i);
	tt=t.substr(0,n-i);
	if(ss==tt)
	{
		cout<<2*(n)-ss.size();
		return 0;
	}
}
cout<<2*n;
}