{ "data": { "question": { "questionId": "3189", "questionFrontendId": "2924", "boundTopicId": null, "title": "Find Champion II", "titleSlug": "find-champion-ii", "content": "
There are n
teams numbered from 0
to n - 1
in a tournament; each team is also a node in a DAG.
You are given the integer n
and a 0-indexed 2D integer array edges
of length m
representing the DAG, where edges[i] = [ui, vi]
indicates that there is a directed edge from team ui
to team vi
in the graph.
A directed edge from a
to b
in the graph means that team a
is stronger than team b
and team b
is weaker than team a
.
Team a
will be the champion of the tournament if there is no team b
that is stronger than team a
.
Return the team that will be the champion of the tournament if there is a unique champion, otherwise, return -1
.
Notes
\n\na1, a2, ..., an, an+1
such that node a1
is the same node as node an+1
, the nodes a1, a2, ..., an
are distinct, and there is a directed edge from the node ai
to node ai+1
for every i
in the range [1, n]
.\n
Example 1:
\n\n\n\n\nInput: n = 3, edges = [[0,1],[1,2]]\nOutput: 0\nExplanation: Team 1 is weaker than team 0. Team 2 is weaker than team 1. So the champion is team 0.\n\n\n
Example 2:
\n\n\n\n\nInput: n = 4, edges = [[0,2],[1,3],[1,2]]\nOutput: -1\nExplanation: Team 2 is weaker than team 0 and team 1. Team 3 is weaker than team 1. But team 1 and team 0 are not weaker than any other teams. So the answer is -1.\n\n\n
\n
Constraints:
\n\n1 <= n <= 100
m == edges.length
0 <= m <= n * (n - 1) / 2
edges[i].length == 2
0 <= edge[i][j] <= n - 1
edges[i][0] != edges[i][1]
a
is stronger than team b
, team b
is not stronger than team a
.a
is stronger than team b
and team b
is stronger than team c
, then team a
is stronger than team c
.0
in the DAG."
],
"solution": null,
"status": null,
"sampleTestCase": "3\n[[0,1],[1,2]]",
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