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[15][15];
bool vis[15];
queue<int> q;
int n,e;
void DFS(int a){
    q.push(a);
    vis[a]=true;
    int i;
    for(i=0;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=0;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=0;i<e;i++){
        scanf("%d %d",&a,&b);
        map[a][b]=map[b][a]=true;
    }
    for(i=0;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(" }
");
            }
        }
    }
    memset(vis,false,sizeof(vis));
    for(i=0;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(" }
");
            }
        }
    }
    return 0;
}