pat05-图1. List Components (25)

05-图1. List Components (25)

时间限制

200 ms

内存限制

65536 kB

代码长度限制

8000 B

判题程序

Standard

作者

CHEN, Yue

For a given undirected graph with N vertices and E edges, please list all the connected components by both DFS and BFS. Assume that all the vertices are numbered from 0 to N-1. While searching, assume that we always start from the vertex with the smallest index, and visit its adjacent vertices in ascending order of their indices.

Input Specification:

Each input file contains one test case. For each case, the first line gives two integers N (0<N<=10) and E, which are the number of vertices and the number of edges, respectively. Then E lines follow, each described an edge by giving the two ends. All the numbers in a line are separated by a space.

Output Specification:

For each test case, print in each line a connected component in the format "{ v1 v2 ... vk }". First print the result obtained by DFS, then by BFS.

Sample Input:

8 6
0 7
0 1
2 0
4 1
2 4
3 5

Sample Output:

{ 0 1 4 2 7 }
{ 3 5 }
{ 6 }
{ 0 1 2 7 4 }
{ 3 5 }
{ 6 }

---

提交代码

 #include<cstdio>
 #include<algorithm>
 #include<iostream>
 #include<cstring>
 #include<queue>
 #include<vector>
 #include<string>
 using namespace std;
 bool map[][];
 bool vis[];
 queue<int> q;
 int n,e;
 void DFS(int a){
     q.push(a);
     vis[a]=true;
     int i;
     for(i=;i<n;i++){
         if(!vis[i]&&map[a][i]){
             DFS(i);
         }
     }
 }
 void BFS(int a){
     queue<int> qq;
     qq.push(a);
     q.push(a);
     vis[a]=true;
     int i;
     while(!qq.empty()){
         a=qq.front();
         qq.pop();
         for(i=;i<n;i++){
             if(!vis[i]&&map[a][i]){
                 vis[i]=true;
                 q.push(i);
                 qq.push(i);
             }
         }
     }
 }
 int main(){
     //freopen("D:\\INPUT.txt","r",stdin);
     int a,b;
     int i;
     scanf("%d %d",&n,&e);
     memset(map,false,sizeof(map));
     memset(vis,false,sizeof(vis));
     for(i=;i<e;i++){
         scanf("%d %d",&a,&b);
         map[a][b]=map[b][a]=true;
     }
     for(i=;i<n;i++){
         if(!vis[i]){
             DFS(i);
             if(!q.empty()){
                 printf("{");//{ 0 1 4 2 7 }
                 while(!q.empty()){
                     printf(" %d",q.front());
                     q.pop();
                 }
                 printf(" }\n");
             }
         }
     }
     memset(vis,false,sizeof(vis));
     for(i=;i<n;i++){
         if(!vis[i]){
             BFS(i);
             if(!q.empty()){
                 printf("{");//{ 0 1 4 2 7 }
                 while(!q.empty()){
                     printf(" %d",q.front());
                     q.pop();
                 }
                 printf(" }\n");
             }
         }
     }
     return ;
 }