In a town, there are n people labeled from 1 to n. There is a rumor that one of these people is secretly the town judge.
If the town judge exists, then:
You are given an array trust where trust[i] = [ai, bi] representing that the person labeled ai trusts the person labeled bi. If a trust relationship does not exist in trust array, then such a trust relationship does not exist.
Return the label of the town judge if the town judge exists and can be identified, or return -1 otherwise.
Examples
Example 1
Input: n = 2, trust = [[1,2]]
Output: 2
Example 2
Input: n = 3, trust = [[1,3],[2,3]]
Output: 3
Example 3
Input: n = 3, trust = [[1,3],[2,3],[3,1]]
Output: -1
Constraints
1 <= n <= 1000
0 <= trust.length <= 104
trust[i].length == 2
All the pairs of trust are unique.
ai != bi
1 <= ai, bi <= n
997. Find the Town Judge
Easy
10 Points
Array
Hash Table
Graph
In a town, there are n people labeled from 1 to n. There is a rumor that one of these people is secretly the town judge.
If the town judge exists, then:
You are given an array trust where trust[i] = [ai, bi] representing that the person labeled ai trusts the person labeled bi. If a trust relationship does not exist in trust array, then such a trust relationship does not exist.
Return the label of the town judge if the town judge exists and can be identified, or return -1 otherwise.
Examples
Example 1
Input: n = 2, trust = [[1,2]]
Output: 2
Example 2
Input: n = 3, trust = [[1,3],[2,3]]
Output: 3
Example 3
Input: n = 3, trust = [[1,3],[2,3],[3,1]]
Output: -1