学步园

#include <iostream>
#include <stdio.h>
#include <queue>
#include <math.h>
#define N 202
using namespace std;
double a[N][N];
int n;
double d[N];
bool f[N];
struct point{
    int x, y;
    }p[202];
double find_edge(int u, int v){
     float dx = p[u].x - p[v].x;
     float dy = p[u].y - p[v].y;
     return sqrt(dx * dx + dy * dy);
}
void dij(){
    int i,j;
    memset(f,0,sizeof(f));
    for(i=1;i<=n;i++){
        d[i]=a[1][i];
        }
    f[1]=1;
    d[1]=0;
    for(i=1;i<n;i++){
        double min=100*100*127;
        int u;
        for(j=1;j<=n;j++){
            if(!f[j]&&d[j]<min){
                min=d[j];
                   u=j;
                }
            }
        if(u==n)return;
        f[u]=1;
        for(j=1;j<=n;j++){
            if(!f[j]){
                if(a[u][j]<=min)
                d[j]=min;
                if(a[u][j]>min){
                    if(d[j]>a[u][j])
                    d[j]=a[u][j];
                    }
                }
            }
        }
    }
int main(){
    int t=1;
    while(cin>>n&&n!=0){
        memset(a,0,sizeof(a));
        int i,j;
        cin>>p[1].x>>p[1].y;
        cin>>p[n].x>>p[n].y;
        if(i>2)
        for(i=2;i<=n-1;i++){
        cin>>p[i].x>>p[i].y;
            }
        for(i=1;i<=n;i++){
            for(j=i+1;j<=n;j++){
                a[i][j]= find_edge(i, j);
                a[j][i]=a[i][j];
                }
            }
        dij();
        printf("Scenario #");
        printf("%d\nFrog Distance = %.3lf\n\n",t++,d[n]);
        }
    return 0;
    }