Doggo Recoloring

Panic is rising in the committee for doggo standardization — the puppies of the new brood have been born multi-colored! In total there are 26 possible colors of puppies in the nature and they are denoted by letters from 'a' to 'z' inclusive.

The committee rules strictly prohibit even the smallest diversity between doggos and hence all the puppies should be of the same color. Thus Slava, the committee employee, has been assigned the task to recolor some puppies into other colors in order to eliminate the difference and make all the puppies have one common color.

Unfortunately, due to bureaucratic reasons and restricted budget, there's only one operation Slava can perform: he can choose a color xx such that there are currently at least two puppies of color xx and recolor all puppies of the color xx into some arbitrary color yy. Luckily, this operation can be applied multiple times (including zero).

For example, if the number of puppies is 77 and their colors are represented as the string "abababc", then in one operation Slava can get the results "zbzbzbc", "bbbbbbc", "aaaaaac", "acacacc" and others. However, if the current color sequence is "abababc", then he can't choose xx='c' right now, because currently only one puppy has the color 'c'.

Help Slava and the committee determine whether it is possible to standardize all the puppies, i.e. after Slava's operations all the puppies should have the same color.

Input

The first line contains a single integer nn (1≤n≤1051≤n≤105) — the number of puppies.

The second line contains a string ss of length nn consisting of lowercase Latin letters, where the ii-th symbol denotes the ii-th puppy's color.

Output

If it's possible to recolor all puppies into one color, print "Yes".

Otherwise print "No".

Output the answer without quotation signs.

Examples

Input

6
aabddc

Output

Yes

Input

3
abc

Output

No

Input

3
jjj

Output

Yes

Note

In the first example Slava can perform the following steps:

1. take all puppies of color 'a' (a total of two) and recolor them into 'b';
2. take all puppies of color 'd' (a total of two) and recolor  them into 'c';
3. take all puppies of color 'b' (three puppies for now) and recolor them into 'c'.

In the second example it's impossible to recolor any of the puppies.

In the third example all the puppies' colors are the same; thus there's no need to recolor anything.

题意：

   有n个小狗，每一种小写字母代表一种颜色，然后颜色的个数在两个以上的就可以染成别的任意颜色，操作次数不限，问你最后能不能把所有的小狗染成同一种颜色。

思路：就是找字符串中存不存在相同的两个字符

        没有考虑到n==1的情况

主要学习一下字符个数记录方法

代码一：

#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<cctype>
#include<map>
#include<set>
#include<vector>
#include<stack>
using namespace std;
typedef long long ll;
map<char,int> m;
int main(){
	string s;
	int n;
	while(~scanf("%d",&n)){
		cin>>s;
		if(n==1){
			cout<<"Yes"<<endl;
			continue;
		} 
		int flag=0;
		m.clear();
		for(int i=0;i<s.length();i++){
			m[s[i]]++;
			if(m[s[i]]>1){
				flag=1;
				break;
		    }
		}
		if(flag) cout<<"Yes"<<endl;
		else     cout<<"No"<<endl;
	}
	return 0;
}

代码二：

#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<cctype>
#include<map>
#include<set>
#include<vector>
#include<stack>
using namespace std;
typedef long long ll;
int vis[30];
int main(){
	int n;
	cin>>n;
	string s;
	cin>>s;
	for(int i=0;i<s.length();i++){
		if(vis[s[i]]){
			cout<<"Yes"<<endl;
			return 0;
		}
		vis[s[i]]=1;
	}
	if(n==1) cout<<"Yes"<<endl;
	else
	 cout<<"No"<<endl;
	return 0;
}