Submission #569219

#	Time	Username	Problem	Language	Result	Execution time	Memory
569219		pavement	Shortcut (IOI16_shortcut)	C++17	0 / 100	1 ms	296 KiB

shortcut

#include "shortcut.h"
#include <bits/stdc++.h>
using namespace std;

using ll = long long;

#define mp make_pair

int n, c;
vector<int> l, d;
vector<ll> P;

ll ans = 1e18;

ll cst(int x, int y) {
	ll ret = 0;
	for (int u = 0; u < n; u++)
		for (int v = 0; v < n; v++)
			ret = max(ret, min({c + max(P[u] - P[x], P[x] - P[u]) + max(P[v] - P[y], P[y] - P[v]), c + max(P[u] - P[y], P[y] - P[u]) + max(P[v] - P[x], P[x] - P[v]), max(P[u] - P[v], P[v] - P[u])}) + d[u] + d[v]);
	return ret;
}

void dnc(int l, int r, int x, int y) {
	if (l > r) return;
	int m = (l + r) >> 1;
	pair<ll, int> opt = mp((ll)1e18, -1);
	for (int i = x; i <= min(m, y); i++)
		opt = min(opt, mp(cst(i, m), i));
	ans = min(ans, opt.first);
	dnc(l, m - 1, x, opt.second);
	dnc(m + 1, r, opt.second, y);
}

ll find_shortcut(int n, vector<int> l, vector<int> d, int c) {
	::n = n;
	::l = l;
	::d = d;
	::c = c;
	P.resize(n);
	for (int i = 1; i < n; i++)
		P[i] = P[i - 1] + l[i - 1];
	dnc(0, n - 1, 0, n - 1);
	return ans;
}

• 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