poj 2253 - Frogger --- dijkstra

http://acm.pku.edu.cn/JudgeOnline/problem?id=2253

 

题目要求就是找出路径中，最小的最大步长！

#include <stdio.h>#include <string.h>#include <math.h>struct {int x;int y;}c[205];float a[205][205];float dis[205];bool used[205];int main (){//freopen ("1.txt","r",stdin);int i,j,k,t,p=0;double d,min,max;while (scanf("%d",&t)!=EOF){if (t==0) return 0;memset(used,0,sizeof(used));for (i=1;i<=t;i++){scanf("%d %d",&c[i].x,&c[i].y);for (j=1;j<i;j++){d=sqrt((float)(c[i].x-c[j].x)*(c[i].x-c[j].x)+(c[i].y-c[j].y)*(c[i].y-c[j].y));a[i][j]=d;a[j][i]=d;}a[i][i]=0;}for (i=1;i<=t;i++)dis[i]=a[1][i];for (i=1;i<=t;i++){min=99999999.9;for (j=1;j<=t;j++){if (!used[j] && dis[j]<min){min=dis[j];k=j;}}used[k]=1;for (j=1;j<=t;j++){max=dis[k]>a[k][j]?dis[k]:a[k][j];if (dis[j]>max)dis[j]=max;}}printf ("Scenario #%d/n",++p);printf ("Frog Distance = %.3f/n/n",dis[2]);}return 0;}