链接：https://codeforces.com/contest/455/problem/A

Alex doesn't like boredom. That's why whenever he gets bored, he comes up with games. One long winter evening he came up with a game and decided to play it.

Given a sequence a consisting of n integers. The player can make several steps. In a single step he can choose an element of the sequence (let's denote it ak) and delete it, at that all elements equal to ak + 1 and ak - 1 also must be deleted from the sequence. That step brings ak points to the player.

Alex is a perfectionist, so he decided to get as many points as possible. Help him.

Input

The first line contains integer n (1 ≤ n ≤ 105) that shows how many numbers are in Alex's sequence.

The second line contains n integers a1, a2, ..., an (1 ≤ ai ≤ 105).

Output

Print a single integer — the maximum number of points that Alex can earn.

Examples

input

Copy

2
1 2

output

Copy

2

input

Copy

3
1 2 3

output

Copy

4

input

Copy

9
1 2 1 3 2 2 2 2 3

output

Copy

10

Note

Consider the third test example. At first step we need to choose any element equal to 2. After that step our sequence looks like this [2, 2, 2, 2]. Then we do 4 steps, on each step we choose any element equals to 2. In total we earn 10 points.

代码：

#include<bits/stdc++.h>
using namespace std;
long long n,t,k;
long long a[100005],s[100005];
map<long long ,long long >m;
main()
{
	cin>>n;
	for(int i=1;i<=n;i++)
	{
		cin>>a[i];
		m[a[i]]++;
	}
	long long flag=0;
	s[0]=0;
	s[1]=m[1];
	for(int i=2;i<=100002;i++)
	{
		s[i]=max(s[i-1],s[i-2]+m[i]*i);
	}
	cout<<s[100002]<<endl;
}