Submission #289369

#	Time	Username	Problem	Language	Result	Execution time	Memory
289369		amoo_safar	Shortcut (IOI16_shortcut)	C++17	31 / 100	2082 ms	6400 KiB

shortcut

#include "shortcut.h"

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

const int N = 3000;
const ll Inf = 1e18;

ll ps[N];
ll maxp[N][N], maxn[N][N];
ll pre[N], suf[N];
ll d[N];
ll n, c;

long long find_shortcut(int _n, vector<int> _l, vector<int> _d, int _c){
	n = _n; c = _c;
	for(int i = 0; i < n; i++) d[i] = _d[i];
	ps[0] = 0;
	for(int i = 1; i < n; i++) ps[i] = ps[i - 1] + _l[i - 1];

	// Calc Maxp
	for(int i = 0; i < n; i++) maxp[i][i] = d[i] + ps[i];
	for(int i = 0; i < n; i++) maxn[i][i] = d[i] - ps[i];
	for(int ln = 2; ln <= n; ln++){
		for(int i = 0; i + ln <= n; i++){
			int j = i + ln - 1;
			maxp[i][j] = max(maxp[i + 1][j], maxp[i][j - 1]);
			maxn[i][j] = max(maxn[i + 1][j], maxn[i][j - 1]);
		}
	}
	// Calc pre
	pre[0] = d[0];
	for(int i = 1; i < n; i++){
		pre[i] = max(pre[i - 1], d[i] + ps[i] + maxn[0][i - 1]);
	}	
	suf[n - 1] = d[n - 1];
	for(int i = n - 2; i >= 0; i--){
		suf[i] = max(suf[i + 1], d[i] - ps[i] + maxp[i + 1][n - 1]);
	}



	ll ans = Inf;

	ll Di, Dj, dia;
	ll cyc;
	for(int i = 0; i < n; i++){
		for(int j = i + 1; j < n; j++){
			Di = ps[i] + maxn[0][i];
			Dj = maxp[j][n - 1] - ps[j];
			cyc = c + ps[j] - ps[i];
			dia = Di + Dj + min(c, cyc - c);
			for(int k = i + 1; k < j; k++){
				for(int k2 = k + 1; k2 < j; k2++){
					dia = max(dia, d[k] + d[k2] + min(ps[k2] - ps[k], cyc - (ps[k2] - ps[k]) ) );
				}
				dia = max(dia, Di + d[k] + min(ps[k] - ps[i], cyc - (ps[k] - ps[i])));
				dia = max(dia, Dj + d[k] + min(ps[j] - ps[k], cyc - (ps[j] - ps[k])));
			}
			dia = max({dia, pre[i], suf[j]});
			ans = min(ans, dia);
		}
	}

	return ans;
}

• Subtask 1: 9 / 9
• Subtask 2: 14 / 14
• Subtask 3: 8 / 8
• Subtask 4: 0 / 7
• Subtask 5: 0 / 33
• Subtask 6: 0 / 22
• Subtask 7: 0 / 4
• Subtask 8: 0 / 3