UVA 208 (DFS)

题意：找出1到T的所有路径；

坑点：一开始以为是到终点，读错了题意，没测试第二个样例，结果WA了4遍，坑大了；

 #include <iostream>
 #include <cmath>
 #include <cstdio>
 #include <cstring>
 #include <cstdlib>
 #include <sstream>
 #include <algorithm>
 #define Max 2147483647
 #define INF 0x7fffffff
 #define N 90000+2
 #define M 40000
 #define ll long long
 #define mem(a,b) memset(a,b,sizeof(a))
 #define repu(i, a, b) for(int i = (a); i < (b); i++)
 #define repd(i, a, b) for(int i = (a-1); i >= (b); i--)
 const double PI=-acos(-1.0);
 using namespace std;
 const int maxn = ;
 int t = , v, sum, T;
 int rec[],vis[];
 int g[][] ,floyd[][];
 void dfs(int x,int n)
 {
     if(x==T)///到终点输出
     {
         printf("%d" ,);
         repu(i,,n-)
         printf(" %d",rec[i]);
         printf(" %d\n",T);
         sum++;
         return ;
     }
     repu(i,,v+)
     {
         if(!vis[i]&&g[x][i]==&&floyd[T][i]!=maxn)
         {///i点能到达终点+x,i通路+未访问过
             rec[n]=i;
             vis[i]=;
             dfs(i,n+);
             vis[i]=;
         }
     }
 }
 int main()
 {
     int x, y, cas = ;
     while (~scanf("%d", &T))
     {
         v = ;
         repu(i,,)
         repu(j,,)
         g[i][j] = floyd[i][j] = maxn;
         while(scanf("%d%d", &x, &y) && (x || y))
         {
             g[x][y] = g[y][x] = ;///无向图
             floyd[x][y] = floyd[y][x] = ;
             v = max(v,max(x,y));///找最大点
         }
         for(int k = ; k <= v; k++)///弗洛伊德算法找最短路，判断两点之间是否是通路
             for (int i = ; i <= v; i++)
                 for (int j = ; j <= v; j++)
                     floyd[i][j] = min(floyd[i][j],floyd[i][k] + floyd[k][j]);
         vis[] = ;
         sum = ;
         printf("CASE %d:\n", cas++);
         dfs(, );///从第一组数找起
         printf("There are %d routes from the firestation to streetcorner %d.\n", sum, T);
     }
     return ;
 }

DFS