# Leetcode 997. Find the Town Judge
###### tags: `Leetcode(C++)`

題目 : https://leetcode.com/problems/find-the-town-judge/submissions/ 。

想法 : 按照題目敘述去找Town Judge，沒有就輸出-1。

時間複雜度 : O(n)。

程式碼 :

class Solution {
public:
    int findJudge(int n, vector<vector<int>>& trust) {
        int l = trust.size(), label[1010] = {0}, label2[1010] = {0}, townJ = 0, ok = 1;
        for(int i=0 ; i<l ; i++){
            label[trust[i][0]] = 1;
        }
        
        for(int i=1 ; i<=n ; i++){
            if(label[i] == 0){
                townJ = i;
            }
        }
        
        if(townJ == 0) return -1;
        
        for(int i=0 ; i<l ; i++){
            if(trust[i][1] == townJ){
                label2[trust[i][0]] = 1;
            }
        }
        
        for(int i=1 ; i<=n ; i++){
            if(label2[i] == 0 && i != townJ){
                return -1;
            }
        }
        
        return townJ;
    }
};