제출 #498632

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
498632		sidon	Dancing Elephants (IOI11_elephants)	C++17	26 / 100	528 ms	2236 KiB

elephants

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

const int MAX_N = 150'000, B = 400, NB = 500, INF = 2e9;

int N, L, X[MAX_N], num[MAX_N], pos[MAX_N];

vector<int> a[NB], b[NB];

void recalculate(int j) {
	auto &c = a[j];
	if(empty(c)) return;
	int sz = size(c), pt = sz;

	for(int i = sz; --i >= 0 ; ) {
		while(pt && X[c[i]] + L < X[c[pt-1]]) --pt;

		num[c[i]] = pt < sz ? num[c[pt]] + 1 : 1;
		pos[c[i]] = pt < sz ? pos[c[pt]] : X[c[i]] + L;
	}
}

void reset() {
	for(int i = 0, j = 0; i < NB; i++) {
		for(int &v : a[i]) pos[j++] = v;
		a[i].clear();
		b[i].clear();
	}
	for(int i = 0; i < N; i++) {
		a[i/B].push_back(pos[i]);
		b[i/B].push_back(X[pos[i]]);
	}
	for(int i = 0; i < NB; i++)
		recalculate(i);
}

void init(int n, int l, int x[]) {
	N = n, L = l;
	for(int i = 0; i < N; i++) {
		X[i] = x[i];
		a[i/B].push_back(i);
	}
	reset();
}

int l, p, q_;

void locate(int i){
	for(l=0; l < NB && size(b[l]) && b[l][0] <= X[i]; l++);
	if(l) l--;
	
	p = lower_bound(begin(b[l]), end(b[l]), X[i]) - begin(b[l]);
}

int update(int i, int y) {
	locate(i);
	while(a[l][p] != i) ++p;
	a[l].erase(begin(a[l]) + p);
	b[l].erase(begin(b[l]) + p);
	recalculate(l);

	X[i] = y;

	locate(i);

	a[l].insert(begin(a[l]) + p, i);
	b[l].insert(begin(b[l]) + p, X[i]);
	recalculate(l);

	if(!(++q_ % B)) reset();

	int res = 0, cur = -1;

	for(int k = 0; k < NB; k++) {
		if(empty(b[k]) || cur >= b[k].back()) continue;

		int j = upper_bound(begin(b[k]), end(b[k]), cur) - begin(b[k]);

		res += num[a[k][j]];
		cur = pos[a[k][j]];
	}

	return res;
}

• Subtask 1: 10 / 10
• Subtask 2: 16 / 16
• Subtask 3: 0 / 24
• Subtask 4: 0 / 47
• Subtask 5: 0 / 3