1142 Maximal Clique (25 分)
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 ))
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:
8 105 67 86 43 64 52 38 22 75 33 464 5 4 3 63 2 8 72 2 31 13 4 3 63 3 2 1
Sample Output:
YesYesYesYesNot MaximalNot a Clique
题目大意:clique是一个点集,在一个无向图中,这个点集中任意两个不同的点之间都是相连的。maximal clique是一个clique,这个clique不可以再加入任何一个新的结点构成新的clique。
输入是有n条边,给出每条边的两端节点,并且后面给出m个查询,查询是点集。
//这个题目大意看了好几遍没看懂,这个clique也不是环,比如对第三个查询2 3,输出Yes,说明不是环了。
//思考了一下发现不太会,怎么去确定这个是maximal的呢?怎么去扩展判断呢?不会。
代码转自:https://www.liuchuo.net/archives/4614
#include#include #include using namespace std;int e[210][210];int main() { int nv, ne, m, ta, tb, k; scanf("%d %d", &nv, &ne); for (int i = 0; i < ne; i++) { scanf("%d %d", &ta, &tb); e[ta][tb] = e[tb][ta] = 1;//存储到邻接矩阵中,有边是1. } scanf("%d", &m); for (int i = 0; i < m; i++) { scanf("%d", &k); vector v(k); int hash[210] = { 0}, isclique = 1, isMaximal = 1; for (int j = 0; j < k; j++) { scanf("%d", &v[j]); hash[v[j]] = 1;//使用hash数组存储 } for (int j = 0; j < k; j++) { //这里判断是否是一个click if (isclique == 0) break;//跳出两层循环 for (int l = j + 1; l < k; l++) { if (e[v[j]][v[l]] == 0) { isclique = 0; printf("Not a Clique\n"); break; } } } if (isclique == 0) continue;//不进行下面的操作。 for (int j = 1; j <= nv; j++) { if (hash[j] == 0) { //挨个判断其他所有的点,判断每一个点。 for (int l = 0; l < k; l++) { //和当前检测中所有的点进行判断。 if (e[v[l]][j] == 0) break;//如果这个点不是的话,接着判断其他点 if (l == k - 1) isMaximal = 0; } } if (isMaximal == 0) { printf("Not Maximal\n"); break; } } if (isMaximal == 1) printf("Yes\n"); } return 0;}
//柳神真厉害。
1.使用邻接矩阵存储图,右边标记为1.
2.对于输入的使用hash数组来标记,向量来存储
3.对图中所有剩下的点一一与当前检测中的进行判断。
//学习了!