Submission #856164

#	Time	Username	Problem	Language	Result	Execution time	Memory
856164		aykhn	Rice Hub (IOI11_ricehub)	C++14	100 / 100	12 ms	4208 KiB

ricehub

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

// author : aykhn

using namespace std;
typedef long long ll;

#define pb push_back
#define ins insert
#define mpr make_pair
#define all(v) v.begin(), v.end()
#define bpc __builtin_popcount
#define pii pair<int, int>
#define pll pair<ll, ll>
#define fi first
#define se second
#define infll 0x3F3F3F3F3F3F3F3F
#define inf 0x3F3F3F3F

vector<ll> pref;

ll getsum(int l, int r)
{
	return pref[r] - pref[l - 1];
}

int besthub(int n, int L, int X[], ll b)
{
	ll x[n + 1];
	pref.assign(n + 1, 0);
	for (int i = 1; i <= n; i++) x[i] = X[i - 1];
	for (int i = 1; i <= n; i++) pref[i] = pref[i - 1] + x[i];
	int ans = 1;
	for (int i = 1; i <= n; i++)
	{
		int l = 1;
		int r = min(i - 1, n - i);
		int best = 0;
		while (l <= r)
		{
			int mid = (l + r) >> 1;
			if (getsum(i + 1, i + mid) - getsum(i - mid, i - 1) <= b)
			{
				best = mid;
				l = mid + 1;
			}
			else r = mid - 1;
		}
		ll sum = getsum(i + 1, i + best) - getsum(i - best, i - 1);
		if (i - best - 1 >= 1 && sum + x[i] - x[i - best - 1] <= b) ans = max(ans, best * 2 + 2);
		else if (i + best + 1 <= n && sum + x[i + best + 1] - x[i] <= b) ans = max(ans, best * 2 + 2);
		else ans = max(ans, best * 2 + 1);
	}
	return ans;
}

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