Submission #580982

#	Time	Username	Problem	Language	Result	Execution time	Memory
580982		8e7	Seats (IOI18_seats)	C++17	100 / 100	3533 ms	69340 KiB

seats

//Challenge: Accepted
#include <bits/stdc++.h>
#include "seats.h"
#pragma GCC optimize("Ofast")
using namespace std;
#ifdef zisk
void debug(){cout << endl;}
template<class T, class ... U> void debug(T a, U ... b){cout << a << " ", debug(b...);}
template<class T> void pary(T l, T r) {
	while (l != r) cout << *l << " ", l++;
	cout << endl;
}
#else
#define debug(...) 0
#define pary(...) 0
#endif
#define ll long long
#define maxn 1000005
#define mod 1000000007
#define pii pair<int, int>
#define ff first
#define ss second
#define io ios_base::sync_with_stdio(0);cin.tie(0);
struct segtree{
	int seg[4*maxn], cnt[4*maxn], tag[4*maxn];
	void push(int cur, int l, int r) {
		seg[cur] += tag[cur];
		if (r - l > 1) {
			tag[cur*2] += tag[cur];
			tag[cur*2+1] += tag[cur];
		}
		tag[cur] = 0;
	}
	void pull(int cur, int l, int r) {
		int m = (l + r) / 2;
		push(cur*2, l, m), push(cur*2+1, m, r);
		seg[cur] = min(seg[cur*2], seg[cur*2+1]);
		cnt[cur] = (seg[cur*2] == seg[cur] ? cnt[cur*2] : 0) + (seg[cur*2+1] == seg[cur] ? cnt[cur*2+1] : 0);
	}
	void init(int cur, int l, int r) {
		if (r <= l) return;
		cnt[cur] = r - l;
		seg[cur] = tag[cur] = 0;
		if (r - l == 1) return;
		int m = (l + r) / 2; 
		init(cur*2, l, m), init(cur*2+1, m, r);
	}
	void modify(int cur, int l, int r, int ql, int qr, int v) {
		if (r <= l || ql >= r || qr <= l) return;
		push(cur, l, r);
		if (ql <= l && qr >= r) {
			tag[cur] += v;
			return;
		}
		int m = (l + r) / 2;
		modify(cur*2, l, m, ql, qr, v);
		modify(cur*2+1, m, r, ql, qr, v);
		pull(cur, l, r);
	}
	int getval(int n) {
		push(1, 0, n);
		if (seg[1] == 4) return cnt[1];
		else return 0;	
	}
} tr;

vector<int> a, pos;
int n;
int m;

void upd(int x, int y, int v) {
	int tmp[4] = {a[x*m+y], a[x*m+y+1], a[(x+1)*m+y], a[(x+1)*m+y+1]};	
	sort(tmp, tmp+4);
	tr.modify(1, 0, n, tmp[0], tmp[1], v);
	tr.modify(1, 0, n, tmp[2], tmp[3], v);
}
void give_initial_chart(int H, int W, vector<int> R, vector<int> C) {
	m = W+2;
	n = H*W;
	tr.init(1, 0, n);
	a.resize((H+2)*(W+2), maxn);
	pos.resize(n);
	for (int i = 0;i < n;i++) {
		R[i]++, C[i]++;
		pos[i] = R[i] * m + C[i];	
		a[R[i] * m + C[i]] = i;
	}
	for (int i = 0;i <= H;i++) {
		for (int j = 0;j <= W;j++) {
			upd(i, j, 1);
		}
	}
}

int swap_seats(int u, int v) {
	int ax = pos[u] / m, ay = pos[u] % m;	
	int bx = pos[v] / m, by = pos[v] % m;	
	for (int i = -1;i <= 0;i++) {
		for (int j = -1;j <= 0;j++) {
			upd(ax+i, ay+j, -1);		
			upd(bx+i, by+j, -1);		
		}
	}
	swap(a[pos[u]], a[pos[v]]);
	for (int i = -1;i <= 0;i++) {
		for (int j = -1;j <= 0;j++) {
			upd(ax+i, ay+j, 1);		
			upd(bx+i, by+j, 1);		
		}
	}
	swap(pos[u], pos[v]);
	return tr.getval(n);
}
/*
2 3 2
0 0
1 0
1 1
0 1
0 2
1 2
0 5
0 5
*/

• Subtask 1: 5 / 5
• Subtask 2: 6 / 6
• Subtask 3: 20 / 20
• Subtask 4: 6 / 6
• Subtask 5: 33 / 33
• Subtask 6: 30 / 30