997. Find the Town Judge
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:
- The town judge trusts nobody.
- Everybody (except for the town judge) trusts the town judge.
- There is exactly one person that satisfies properties 1 and 2.
You are given an array trust where trust[i] = [ai, bi] representing that the person labeled ai trusts the person labeled bi.
Return the label of the town judge if the town judge exists and can be identified, or return -1 otherwise.
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 <= 10000 <= trust.length <= 104trust[i].length == 2- All the pairs of
trustare unique. ai != bi1 <= ai, bi <= n
Solution:
class Solution {
public:
int findJudge(int n, vector<vector<int>>& edges) {
int ans =-1;
vector <int> ind(n+1);
vector <int> out(n+1);
for(int i=0; i<edges.size(); i++){
out[edges[i][0]]++;
ind[edges[i][1]]++;
}
for(int i=0; i<ind.size(); i++){
if((ind[i]==n-1)&&(out[i]==0)){
ans = i;
// break;
}
}
return ans;
}
};
Happy Coding ;