Submission #958885

#	Time	Username	Problem	Language	Result	Execution time	Memory
958885		MinaRagy06	Shortcut (IOI16_shortcut)	C++17	0 / 100	2 ms	8792 KiB

shortcut

#include <bits/stdc++.h>
#include "shortcut.h"
#ifdef MINA
#include "grader.cpp"
#endif
using namespace std;
#define ll long long

const int N = 3005;
ll v1[N][N], v2[N][N], v3[N][N], v4[N][N];
ll find_shortcut(int n, vector<int> l, vector<int> a, int c) {
	reverse(l.begin(), l.end()), l.push_back(0), reverse(l.begin(), l.end()), l.push_back(0);
	reverse(a.begin(), a.end()), a.push_back(-1), reverse(a.begin(), a.end());
	ll prf[n + 2]{};
	for (int i = 2; i <= n; i++) {
		prf[i] = prf[i - 1] + l[i - 1];
	}
	auto check = [&] (ll t) {
		for (int i = 1; i <= n; i++) {
			for (int j = i + 1; j <= n; j++) {
				if (prf[j] - prf[i] + a[i] + a[j] <= t) {
					v1[i][j] = v2[i][j] = v3[i][j] = v4[i][j] = 1e18;
					continue;
				}
				v1[i][j] = t + prf[j] - prf[i] - a[i] - a[j];
				v2[i][j] = t - prf[j] + prf[i] - a[i] - a[j];
				v3[i][j] = t + prf[i] + prf[j] - a[i] - a[j];
				v4[i][j] = t - prf[i] - prf[j] - a[i] - a[j];
			}
		}
		for (int x = 1; x <= n; x++) {
			for (int y = x + 1; y <= n; y++) {
				ll mn1 = 1e18, mn2 = 1e18, mn3 = 1e18, mn4 = 1e18;
				ll len = prf[y] - prf[x] + c;
				for (int i = 1; i <= n; i++) {
					for (int j = i + 1; j <= n; j++) {
						if (x <= i && j <= y) {
							mn1 = min(mn1, v1[i][j]);
						} else if (i < x && y < j) {
							mn2 = min(mn2, v2[i][j]);
						} else if (i <= x && x <= j && j <= y) {
							mn3 = min(mn3, v3[i][j]);
						} else if (x <= i && i <= y && y <= j) {
							mn4 = min(mn4, v4[i][j]);
						}
					}
				}
				if (len <= mn1 && -(prf[y] - prf[x]) + c <= mn2 && len + 2 * prf[x] <= mn3 && len - 2 * prf[y] <= mn4) {
					return 1;
				}
			}
		}
		return 0;
	};
	ll s = 0, e = 1ll << 42;
	while (s <= e) {
		ll md = (s + e) >> 1;
		if (check(md)) {
			e = md - 1;
		} else {
			s = md + 1;
		}
	}
	return s;
}

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