CodeForces 455A

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 a_k) and delete it, at that all elements equal to a_k + 1 and a_k - 1 also must be deleted from the sequence. That step brings a_k 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, ..., a_n (1 ≤ a_i ≤ 10⁵).

Output

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

Example Input 2 1 2 Output 2 Input 3 1 2 3 Output 4 Input 9 1 2 1 3 2 2 2 2 3 Output 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.

// // Created by liyuanshuo on 2017/3/12. // #include <iostream> #include <cstdio> #include <cstring> using namespace std; const int maxn = 1e5+10; int64_t dp[maxn], res[maxn]; int mainC( ) { //freopen ( "F:\\CSLeaning\\Thinking in C++\\C402\\in.in", "r", stdin ); memset (dp, 0, sizeof (dp)); memset (res, 0, sizeof (res)); int n, a; cin>>n; for (int i = 0; i < n ; ++i) { cin>>a; //scanf ("%d", &a); dp[a]++; } res[1] = dp[1]; for (int j = 2; j <= 100002; ++j) { res[j] = max ( res[j-1], res[j-2]+dp[j]*j ); } cout<<res[100002]<<endl; return 0; }