CF1463E.Plan of Lectures

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题目描述

Ivan is a programming teacher. During the academic year, he plans to give nn lectures on nn different topics. Each topic should be used in exactly one lecture. Ivan wants to choose which topic will he explain during the 11 -st, 22 -nd, ..., nn -th lecture — formally, he wants to choose some permutation of integers from 11 to nn (let's call this permutation qq ). qiq_i is the index of the topic Ivan will explain during the ii -th lecture.

For each topic (except exactly one), there exists a prerequisite topic (for the topic ii , the prerequisite topic is pip_i ). Ivan cannot give a lecture on a topic before giving a lecture on its prerequisite topic. There exists at least one valid ordering of topics according to these prerequisite constraints.

Ordering the topics correctly can help students understand the lectures better. Ivan has kk special pairs of topics (xi,yi)(x_i, y_i) such that he knows that the students will understand the yiy_i -th topic better if the lecture on it is conducted right after the lecture on the xix_i -th topic. Ivan wants to satisfy the constraints on every such pair, that is, for every i[1,k]i \in [1, k] , there should exist some j[1,n1]j \in [1, n - 1] such that qj=xiq_j = x_i and qj+1=yiq_{j + 1} = y_i .

Now Ivan wants to know if there exists an ordering of topics that satisfies all these constraints, and if at least one exists, find any of them.

输入格式

The first line contains two integers nn and kk ( 2n31052 \le n \le 3 \cdot 10^5 , 1kn11 \le k \le n - 1 ) — the number of topics and the number of special pairs of topics, respectively.

The second line contains nn integers p1p_1 , p2p_2 , ..., pnp_n ( 0pin0 \le p_i \le n ), where pip_i is the prerequisite topic for the topic ii (or pi=0p_i = 0 if the ii -th topic has no prerequisite topics). Exactly one of these integers is 00 . At least one ordering of topics such that for every ii the pip_i -th topic is placed before the ii -th topic exists.

Then kk lines follow, the ii -th line contains two integers xix_i and yiy_i ( 1xi,yin1 \le x_i, y_i \le n ; xiyix_i \ne y_i ) — the topics from the ii -th special pair. All values of xix_i are pairwise distinct; similarly, all valus of yiy_i are pairwise distinct.

输出格式

If there is no ordering of topics meeting all the constraints, print 00 .

Otherwise, print nn pairwise distinct integers q1q_1 , q2q_2 , ..., qnq_n ( 1qin1 \le q_i \le n ) — the ordering of topics meeting all of the constraints. If there are multiple answers, print any of them.

输入输出样例

  • 输入#1

    5 2
    2 3 0 5 3
    1 5
    5 4

    输出#1

    3 2 1 5 4
  • 输入#2

    5 2
    2 3 0 5 3
    1 5
    5 1

    输出#2

    0
  • 输入#3

    5 1
    2 3 0 5 3
    4 5

    输出#3

    0
  • 输入#4

    5 4
    2 3 0 5 3
    2 1
    3 5
    5 2
    1 4

    输出#4

    3 5 2 1 4
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