Submission #999219

#	Time	Username	Problem	Language	Result	Execution time	Memory
999219		ByeWorld	Cigle (COI21_cigle)	C++14	100 / 100	211 ms	117720 KiB

cigle

#include <bits/stdc++.h>
#include <random>
#define ll long long
#define int long long
#define fi first
#define se second
#define pb push_back
#define md ((l+r)>>1)
#define lf (id<<1)
#define rg ((id<<1)|1)
#define ld long double
using namespace std;
typedef pair<int,int> pii;
typedef pair<pii,pii> ipii;
const int MAXN = 5e3+10;
const int MAXA = 1e6+10;
const int INF = 2e9+10;
const int LOG = 30;
const int MOD = 1e9+7;
void chmx(int &a, int b){
	a = max(a, b);
}

int n;
int a[MAXN], pr[MAXN], dp[MAXN][MAXN];


signed main() {
	// ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
	cin >> n;
	for(int i=1; i<=n; i++){
		cin >> a[i];
	}
	for(int p=1; p<=n-1; p++){
		pr[1] = dp[1][p];
		for(int i=2; i<=p; i++){
			pr[i] = max(pr[i-1], dp[i][p]);
		}

		int l = p, r = p+1, top = 0, bot = 0, cnt = -1;
		while(l>=1 && r<=n){
			if(top==bot){
				cnt++; 
				chmx(dp[p+1][r], pr[l]+cnt); // max dp[...][l-1]
				top += a[l--]; bot += a[r++];
			} else if(top < bot){
				top += a[l--];
			} else if(top > bot){
				bot += a[r++];
			}
		}

		for(int i=p+1; i<=n; i++) chmx(dp[p][i], dp[p][i-1]); 
	}

	int ANS = 0;
	for(int i=1; i<=n; i++) ANS = max(ANS, dp[i][n]);
	cout << ANS << '\n';
}

• Subtask 1: 9 / 9
• Subtask 2: 11 / 11
• Subtask 3: 13 / 13
• Subtask 4: 15 / 15
• Subtask 5: 52 / 52