Submission #781198

#	Time	Username	Problem	Language	Result	Execution time	Memory
781198		zsombor	Rice Hub (IOI11_ricehub)	C++17	100 / 100	26 ms	3352 KiB

ricehub

#include <iostream>
#include <vector>
#include "ricehub.h"
using namespace std;
using ll = long long;

int n, ans;
ll m;
vector <ll> r(1e5 + 1, 0);
vector <ll> p(1e5 + 1, 0);

ll sum(int L, int R) {
	return p[R] - p[L - 1];
}

ll distL(int i, int cnt) {
	int L = i - cnt < 1 ? 1 : i - cnt;
	return r[i] * (i - L) - sum(L, i - 1);
}

ll distR(int i, int cnt) {
	int R = i + cnt > n ? n : i + cnt;
	return sum(i + 1, R) - r[i] * (R - i);
}

ll dist(int i, int cnt) {
	return distL(i, cnt) + distR(i, cnt);
}

void solve(int i) {
	int a = 0, b = n, c;
	while (b - a > 1) {
		c = (a + b) / 2;
		dist(i, c) <= m ? a = c : b = c;
	}
	int L = max(1, i - a), R = min(n, i + a);
	ans = max(ans, R - L + 1);
	if (L > 1 && dist(i, a) + r[i] - r[L - 1] < m) ans = max(ans, R - L + 2);
	if (R < n && dist(i, a) + r[R + 1] - r[i] < m) ans = max(ans, R - L + 2);
}

int besthub(int N, int L, int R[], ll M) {
	n = N; m = M;
	for (int i = 1; i <= n; i++) {
		r[i] = R[i - 1];
		p[i] = p[i - 1] + r[i];
	}
	for (int i = 1; i <= n; i++) solve(i);
	return ans;
}

• Subtask 1: 17 / 17
• Subtask 2: 25 / 25
• Subtask 3: 26 / 26
• Subtask 4: 32 / 32