Card game

#include <bits/stdc++.h>

using namespace std;

//Definitions for quicker writing
#define REP(i,a,b) for (int i = a; i < b; i++)

//Typedefs for quicker writing
typedef long long ll;
typedef vector<int> vi;
typedef pair<int,int> pi;


int main() {
	//IO optimization
	ios::sync_with_stdio(0);
	cin.tie(0);
	
	//Input definition
	int n;

	cin >> n;
	
	if(n<3){
		cout << 0 << "\n";
		return 0;
	}

    	int cards[n];
    	REP(i,0,n){
        	cin >> cards[i];
    	}

	//Main part
	int best[n+1];
	best[0] = 0;
	best[1] = 0;
	best[2] = 0;
		
	REP(i,3,n+1){
		best[i] = max(best[i-1], best[i-3]+cards[i-2]);
	}

	//Write out
	//REP(i,0,n+1){
	//	cout << i << ": " << best[i] <<"\n";
	//}
	cout << best[n] << "\n";	

	//Return
	return 0;

}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: ACCEPTED

Test 13

Verdict: ACCEPTED

Test 14

Verdict: ACCEPTED

Test 15

Verdict: ACCEPTED