PAT 1146. Topological Order (25) – 甲级

This is a problem given in the Graduate Entrance Exam in 2018: Which of the following is NOT a topological order obtained from the given directed graph? Now you are supposed to write a program to test each of the options.
Input Specification:
Each input file contains one test case. For each case, the first line gives two positive integers N (<= 1,000), the number of vertices in the graph, and M (<= 10,000), the number of directed edges. Then M lines follow, each gives the start and the end vertices of an edge. The vertices are numbered from 1 to N. After the graph, there is another positive integer K (<= 100). Then K lines of query follow, each gives a permutation of all the vertices. All the numbers in a line are separated by a space.
Output Specification:
Print in a line all the indices of queries which correspond to “NOT a topological order”. The indices start from zero. All the numbers are separated by a space, and there must no extra space at the beginning or the end of the line. It is graranteed that there is at least one answer.
Sample Input:
6 8
1 2
1 3
5 2
5 4
2 3
2 6
3 4
6 4
5
1 5 2 3 6 4
5 1 2 6 3 4
5 1 2 3 6 4
5 2 1 6 3 4
1 2 3 4 5 6
Sample Output:
3 4

题目大意:给一个有向图,判断给定序列是否是拓扑序列~
分析:用邻接表v存储这个有向图,并将每个节点的入度保存在in数组中。对每一个要判断是否是拓扑序列的结点遍历,如果当前结点的入度不为0则表示不是拓扑序列,每次选中某个点后要将它所指向的所有结点的入度-1,最后根据是否出现过入度不为0的点决定是否要输出当前的编号i~flag是用来判断之前是否输出过现在是否要输出空格的~judge是用来判断是否是拓扑序列的~

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