Submission #1003130

#	Time	Username	Problem	Language	Result	Execution time	Memory
1003130		coolboy19521	Rice Hub (IOI11_ricehub)	C++17	0 / 100	13 ms	2140 KiB

ricehub

#include "bits/stdc++.h"
#include "ricehub.h"
#define i64 long long
 
using namespace std;
 
const int sz = 2e5 + 10;
 
int a[sz];
int n;
i64 b;
 
bool che(int x) {
	int ra = x / 2;
	int ps = ra;
	i64 sm = 0;
	for (int i = 0; i < x; i ++) {
		sm += abs(a[i] - a[ps]);
	}
	if (sm <= b) {
		return true;
	}
	ps ++;
	for (; ps < n - ra; ps ++) {
		int pps = ps - 1; // previous ps
		sm -= abs(a[pps - ra] - a[pps]); // delete leftmost
		sm -= abs(a[pps] - a[ps]); // delete new ps
		sm -= (ra - 1); // distance to right decreases
		sm += abs(a[pps] - a[ps]); // add previous ps
		sm += (ra - 1); // distance to left increases
		sm += abs(a[ps + ra] - a[ps]); // add rightmost
		if (sm <= b) {
			return true;
		}
	}
	return false;
}

bool chee(int x) {
	int lra = x / 2 - 1;
	int rra = x / 2;
	int ps = lra;
	i64 sm = 0;
	for (int i = 0; i < x; i ++) {
		sm += abs(a[i] - a[ps]);
	}
	if (sm <= b) {
		return true;
	}
	for (; ps < n - rra; ps ++) {
		int pps = ps - 1;
		sm -= abs(a[pps - lra] - a[pps]); // delete leftmost
		sm -= abs(a[pps] - a[ps]); // delete new ps
		sm -= (rra - 1); // distance to right decreases
		sm += abs(a[pps] - a[ps]); // add previous ps
		sm += (lra - 1); // distance to left increases
		sm += abs(a[ps + rra] - a[ps]); // add rightmost
		if (sm <= b) {
			return true;
		}
	}
	return false;
}
 
int besthub(int R, int L, int X[], long long B)
{
	int le, ri;
	le = 0, ri = R + 1;
 
	for (int i = 0; i < R; i ++) {
		a[i] = X[i];
	}
 
	b = B;
	n = R;
 
	while (1 < ri - le) {
		int mi = le + (ri - le) / 2;
 
		bool b = (mi % 2) ? che(mi) : chee(mi);

		if (b) {
			le = mi;
		} else {
			ri = mi;
		}
	}
 
	return le;
}

• Subtask 1: 0 / 17
• Subtask 2: 0 / 25
• Subtask 3: 0 / 26
• Subtask 4: 0 / 32