Submission #125409

#	Time	Username	Problem	Language	Result	Execution time	Memory
125409		nhho	Mountains (IOI17_mountains)	C++14	100 / 100	36 ms	14328 KiB

mountains

#include <bits/stdc++.h>
#include "mountains.h"

using namespace std;

constexpr int MAX = 2000;
int dp[MAX][MAX];

bool CanSee(int a, int b, int c, vector<int>& y) {
	return (long long)(y[c] - y[a]) * (b - a) >= (long long)(y[b] - y[a]) * (c - a);
}

int maximum_deevs(vector<int> y) {
	int n = y.size();
	for (int i = 0; i < n; i++) {
		dp[i][i] = 1;
		int la = i, add = 1;
		for (int j = i - 1; j >= 0; j--)
			if (la == i || CanSee(j, la, i, y)) {
				add += dp[j + 1][la - 1];
				la = j;
				dp[j][i] = max(dp[j][i - 1], add);
			} else
				dp[j][i] = max(dp[j][i - 1], dp[j][la - 1] + add);
	}
	// for (int i = 0; i < n; i++) {for (int j = 0; j <= i; j++) printf("%d ", dp[j][i]); puts("");}
	return dp[0][n - 1];
}

• Subtask 1: 20 / 20
• Subtask 2: 20 / 20
• Subtask 3: 30 / 30
• Subtask 4: 30 / 30