Submission #18840

#	Time	Username	Problem	Language	Result	Execution time	Memory
18840		ggoh	Ideal city (IOI12_city)	C++98	32 / 100	203 ms	22092 KiB

city

#include<cstdio>
#include<map>
#include<queue>
int a,x,y,p,q,i,j,dx[]={1,0,-1,0},dy[]={0,1,0,-1};
long long sum,mod=1e9;
bool m[2002][2002];
std::queue<int>P,Q;
int DistanceSum (int N, int *X, int *Y)
{
    a=N;
    x=2147483647;y=2147483647;
    for(i=0;i<a;i++)x=std::min(x,X[i]),y=std::min(y,Y[i]);
    for(i=0;i<a;i++)X[i]-=x,Y[i]-=y,m[X[i]][Y[i]]=1;
    if(a<=2000)
    {
        int D[2002][2002];
        for(i=0;i<a;i++)
        {
            P.push(X[i]);
            Q.push(Y[i]);
            for(j=0;j<a;j++)D[X[j]][Y[j]]=0;
            D[X[i]][Y[i]]=1;sum++;
            while(!P.empty())
            {
                p=P.front();P.pop();q=Q.front();Q.pop();
                for(int k=0;k<4;k++)
                {
                    x=p+dx[k];y=q+dy[k];
                    if(x>=0&&y>=0&&m[x][y]&&D[x][y]==0)
                    {
                        D[x][y]=D[p][q]+1;
                        sum+=D[x][y];
                        P.push(x);Q.push(y);
                    }
                }
            }
            sum-=a;
        }
        sum/=(long long)2;
    }
    else
    {
        long long xsum[100002]={},ysum[100002]={};
        long long xx,yy;
        for(i=0;i<a;i++)
        {
            xsum[X[i]]++;ysum[Y[i]]++;
        }
        xx=xsum[0];yy=ysum[0];
        for(i=1;i<a;i++)
        {
            sum+=xx*(long long)xsum[i];
            xsum[i]+=xsum[i-1];
            xx+=xsum[i];
            sum+=yy*(long long)ysum[i];
            ysum[i]+=ysum[i-1];
            yy+=ysum[i];
        }
        sum/=(long long)2;
    }
    return sum%mod;
}

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