Submission #576452

#	Time	Username	Problem	Language	Result	Execution time	Memory
576452		benson1029	Ideal city (IOI12_city)	C++14	11 / 100	1093 ms	5172 KiB

city

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

struct hash_pair{
	size_t operator()(const pair<int,int> &x) const {
		auto hash1 = hash<int>{}(x.first);
		auto hash2 = hash<int>{}(x.second+12345);
		return hash1^hash2;
	}
};

unordered_map< pair<int,int>, int, hash_pair > mp, vis, dis;
queue< pair<int,int> > q;
int dx[4] = {0, 0, 1, -1};
int dy[4] = {1, -1, 0, 0};



int DistanceSum(int N, int *X, int *Y) {
	mp.reserve(2*N); vis.reserve(2*N); dis.reserve(2*N);
	for(int i=0; i<N; i++) {
		mp[{X[i], Y[i]}] = 1;
	}
	long long ans = 0;
	for(int i=0; i<N; i++) {
		for(int j=0; j<N; j++) vis[{X[j], Y[j]}] = 0;
		vis[{X[i], Y[i]}] = 1;
		q.push({X[i], Y[i]});
		dis[{X[i], Y[i]}] = 0;
		while(!q.empty()) {
			int x = q.front().first;
			int y = q.front().second;
			ans += dis[{x, y}];
			q.pop();
			for(int j=0; j<4; j++) {
				if(mp[{x+dx[j], y+dy[j]}] == 1 && vis[{x+dx[j], y+dy[j]}] == 0) {
					vis[{x+dx[j], y+dy[j]}] = 1;
					dis[{x+dx[j], y+dy[j]}] = dis[{x, y}] + 1;
					q.push({x+dx[j], y+dy[j]});
				}
			}
		}
	}
	return (ans/2) % 1000000000;
}

• Subtask 1: 11 / 11
• Subtask 2: 0 / 21
• Subtask 3: 0 / 23
• Subtask 4: 0 / 45