A clique is a subset of vertices of an undirected graph such that every two distinct vertices in the clique are adjacent. A maximal clique is a clique that cannot be extended by including one more adjacent vertex. (Quoted from https://en.wikipedia.org/wiki/Clique_(graph_theory))
Now it is your job to judge if a given subset of vertices can form a maximal clique.
Input Specification:
Each input file contains one test case. For each case, the first line gives two positive integers Nv (≤ 200), the number of vertices in the graph, and Ne, the number of undirected edges. Then Ne lines follow, each gives a pair of vertices of an edge. The vertices are numbered from 1 to Nv.
After the graph, there is another positive integer M (≤ 100). Then M lines of query follow, each first gives a positive number K (≤ Nv), then followed by a sequence of K distinct vertices. All the numbers in a line are separated by a space.
Output Specification:
For each of the M queries, print in a line Yes
if the given subset of vertices can form a maximal clique; or if it is a clique but not a maximal clique, print Not Maximal
; or if it is not a clique at all, print Not a Clique
.
Sample Input:
8 10
5 6
7 8
6 4
3 6
4 5
2 3
8 2
2 7
5 3
3 4
6
4 5 4 3 6
3 2 8 7
2 2 3
1 1
3 4 3 6
3 3 2 1
Sample Output:
Yes
Yes
Yes
Yes
Not Maximal
Not a Clique
在一个无向图中,如果在给定的顶点集中任意两个不同的点之间都有一条边,那么我们称这样的点集为Clique。如果一个clique点集不可以再加入任何一个新的结点构成新的clique,我们称这样的Clique为maximal Clique。给定一个无向图和M个查询,问对于每一个查询中的点集是否是maximal Clique,如果不是,是否是Clique。
方法:对于每一组输入的测试样例,依次遍历两两结点之间是否存在路径,如果有一个不存在,则不是Clique;若是,则依次遍历未在该样例中的结点,若存在一个结点与样例中的结点之间都有路径,则不是maximal Clique,否则是
满分代码如下:
#include<bits/stdc++.h>
using namespace std;
const int N=205;
int e[N][N],nv,ne,m,k,vst[N];
int main(){
for(int i=0;i<N;i++){
for(int j=0;j<N;j++){
e[i][j]=0;
}
}
scanf("%d%d",&nv,&ne);
int u,v;
for(int i=1;i<=ne;i++){
scanf("%d%d",&u,&v);
e[u][v]=e[v][u]=1;
}
scanf("%d",&m);
for(int i=1;i<=m;i++){
int clique=1,max_c=1;
memset(vst,0,sizeof(vst));
scanf("%d",&k);
vector<int> ve(k);
for(int j=0;j<k;j++){
scanf("%d",&ve[j]);
vst[ve[j]]=1;
}
for(int j=0;j<k;j++){
for(int l=j+1;l<k;l++){
if(e[ve[j]][ve[l]]==0){
clique=0;
break;
}
}
if(clique==0) break;
}
for(int j=1;j<=nv;j++){
if(vst[j]==0){
for(int l=0;l<k;l++){
if(e[j][ve[l]]==0)
break;
if(l==k-1){
max_c=0;
break;
}
}
}
if(max_c==0) break;
}
if(clique==0){
printf("Not a Clique\n");
continue;
}
if(max_c==0){
printf("Not Maximal\n");
continue;
}
printf("Yes\n");
}
return 0;
}