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 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include<stdio.h>
#include<string.h>

int main(void){
	int n,i,j,ret,l,corr,flg,max;
	char s[128],t[128];
	
	scanf("%d%*c",&n);
	scanf("%s%*c",s);
	scanf("%s%*c",t);
	//printf("%d\n",strlen(s));
	corr=0;
	flg=0;
	max=0;
	for(i=0;i<n;i++){
		if(s[i]==t[0]){
			for(j=0;j<n;j++){
				//printf("%d %d\n",i+j,j);
				//printf("%c %c\n",s[i+j],t[j]);
				if(s[i+j]!=t[j]){
					corr=0;
					break;
				}else{
					corr++;
					//printf("corr:%d\n",corr);
					//printf("%d / %d\n",i+j,n);
					if(i+j==n-1){
						flg=1;
						break;
					}
				}
			}
		}
		if(max<corr){
			max=corr;
			flg=0;
		}
	}
	printf("%d\n",2*n-max);
	return 0;
}