Submission #316842

#	Time	Username	Problem	Language	Result	Execution time	Memory
316842		amunduzbaev	Ideal city (IOI12_city)	C++14	55 / 100	169 ms	16252 KiB

city

//#include "grader.cpp"
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pb push_back
const int N=2005, mod= 1e9;
int n, dist[N][N];
vector<vector<int>> edges(2005);

void Dijkstra(int cur){
	queue<int>q;
	q.push(cur);
	while(!q.empty()){
		int u=q.front(); q.pop();
		for(auto x:edges[u]){
			if(dist[cur][u]+1 < dist[cur][x]){
			dist[cur][x] = dist[cur][u]+1;
			q.push(x);
			}
		}
	}
}
const int NAX = 1e5+5;
int sufx[NAX], sufy[NAX];

int DistanceSum(int N, int *x, int *y) {
	n=N;
	
	if(n<=2000){
		for(int i=0;i<n;i++){
			for(int j=i+1;j<n;j++){
				dist[i][j]=2e9;
				dist[j][i]=2e9;
				if(abs(x[i]-x[j]) + abs(y[i]-y[j]) == 1){
					edges[i].pb(j);
					edges[j].pb(i);
				}
			}
		}

		for(int i=0;i<n;i++)
			Dijkstra(i);

		ll ans=0;
		for(int i=0; i<n; i++){
			for(int j=i+1; j<n; j++){
				ans += dist[i][j];
				ans %= mod;
			}
		}
 		return ans;
	}
	
	else{
		sort(x,x+n);
		sort(y,y+n);
		for(int i=n-2; i>=0; i--){
			sufx[i] += sufx[i+1] + x[i+1];
			sufy[i] += sufy[i+1] + y[i+1];
		}
		ll ans=0;
		for(int i=0;i<n;i++){
			int cur=x[i]*(n-i-1);
			ans+=(sufx[i]-cur);
			ans%=mod;
		}
		for(int i=0;i<n;i++){
			int cur=y[i]*(n-i-1);
			ans+=(sufy[i]-cur);
			ans%=mod;
		}
		return ans;
	}
}

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