python C++計算 indegree解Leetcode 997 Find the Town Judge

python C++計算 indegree解Leetcode 997  Find the Town Judge

使用圖形解決方案。

由於信任中的每一對 e=(a, b) 實際上表示一種信任關係，可以將其視為有向邊。C++程式請進

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Use graph solution.

Since each pair e=(a, b) in trust denotes in fact a trusting relation which can be consider as a directed edge.

[codes on Leecode]https://leetcode.com/problems/find-the-town-judge/solutions/4764867/graph-solution-indeg-outdeg-array-vs-hash-table-81ms-beats-100/

[Leetcode playList]https://www.youtube.com/watch?v=WjrWkPysfRM&list=PLYRlUBnWnd5IdDHk2BjqXwesydU17z_xk

[Dynamic Programming Playlist]https://www.youtube.com/watch?v=30yq3fmE6E8&list=PLYRlUBnWnd5K_XYUesV9oc6M9ONXII61T

#pragma GCC optimize("O3", "unroll-loops")
class Solution {
public:
   int findJudge(int n, vector<vector<int>>& trust) {
      int trusting[1001]={0}, trusted[1001]={0};//1 <= n <= 1000
      for (vector<int>& e: trust){
          trusting[e[0]]++; //outdeg
          trusted[e[1]]++; // indeg
      }
      for(int i=1; i<=n; i++)
         if (trusting[i]==0 && trusted[i]==n-1) return i;
     return -1; 
  }
};