POJ2502-Subway

http://poj.org/problem?id=2502

好像不是我写的- -？风格略不像啊

#include<iostream>
#include<cstdio>
#include<cstring>
#include<cmath>
#include<cstdlib>
#define maxn 205
using namespace std;
struct Point
{
    double x, y;
}point[maxn];

double map[maxn][maxn],subv, walkv;
int n;
double dist(Point &a,Point &b)
{
    Point p;
    p.x=a.x-b.x;
    p.y=a.y-b.y;
    return sqrt(p.x*p.x+p.y*p.y);
}
void input()
{
    int i,j;
    Point last,now;
    for(i=0;i<2;i++)
       scanf("%lf%lf",&point[i].x,&point[i].y);
    n=2;
    last.x=last.y=-1;
    while(scanf("%lf%lf",&now.x,&now.y)!=EOF)
    {
        if(!(now.x==-1&&now.y==-1))
        {
            point[n++]=now;
            if(!(last.x==-1&&last.y==-1))
               map[n-1][n-2]=map[n-2][n-1]=dist(point[n-1],point[n-2])/subv;
        }
        last=now;
    }
    for(i=0;i<n;i++)
       for(j=0;j<n;j++)
          if(map[i][j]==-1)
             map[i][j]=dist(point[i],point[j])/walkv;
}
void floyd()
{
    int i,j,k;
    for(k=0;k<n;k++)
       for(i=0;i<n;i++)
          for(j=0;j<n;j++)
             map[i][j]=min(map[i][j],map[i][k]+map[k][j]);
}
int main(void)
{
    int i,j;
    for(i=0;i<maxn;i++)
       for(j=0;j<maxn;j++)
          map[i][j]=-1;
    subv=40*1000.0/60;
    walkv=10*1000.0/60;
    input();
    floyd();
    printf("%.0f\n",map[0][1]);
    return 0;
}