Submission #1021787

#	Time	Username	Problem	Language	Result	Execution time	Memory
1021787		vjudge1	Ideal city (IOI12_city)	C++17	55 / 100	119 ms	2164 KiB

city

#include<bits/stdc++.h>
using namespace std;
int mod=1e9;
long long ANS;
bitset<2010>done;
queue<pair<int,int>>q;
vector<int>adj[2010];
map<pair<int,int>,int>S;
void flod(){
    while(q.size()) {
        auto[x,d]=q.front();
        q.pop();
        if(done[x])continue;
        done[x]=1;ANS+=d;
        for(auto i:adj[x])
            q.push({i,d+1});
    }
}
int DistanceSum(int N, int *X, int *Y) {
    if(N>2000){
        sort(X,X+N);
        sort(Y,Y+N);
        long long ans=0;
        for(long long i=0;i<N;i++){
            ans+=i*X[i] - (N-i-1) *X[i];
            ans%=mod;
        }
        for(long long i=0;i<N;i++){
            ans+=i*Y[i] - (N-i-1) *Y[i];
            ans%=mod;
        }
        return (ans+mod)%mod;
    }
    int A=*min_element(Y,Y+N);
    int B=*min_element(X,X+N);
    for(int i=0;i<N;i++)
        S[{X[i]-=B,Y[i]-=A}]=i;
    for(int i=0;i<N;i++){
        if(S.count({X[i]-1,Y[i]}))
            adj[i].push_back(S[{X[i]-1,Y[i]}]);
        if(S.count({X[i]+1,Y[i]}))
            adj[i].push_back(S[{X[i]+1,Y[i]}]);
        if(S.count({X[i],Y[i]-1}))
            adj[i].push_back(S[{X[i],Y[i]-1}]);
        if(S.count({X[i],Y[i]+1}))
            adj[i].push_back(S[{X[i],Y[i]+1}]);
    }
    for(int i=0;i<N;i++){
        q.push({i,0});
        flod();
        done.reset();
    }
    return ANS/2%mod;
}

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