LC1583-统计不开心的朋友

1583. 统计不开心的朋友

不开心的朋友算我一个

按题意做就好了

class Solution {
public:
    int unhappyFriends(int n, vector<vector<int>>& preferences, vector<vector<int>>& pairs) {
        vector<vector<int>>f(n + 1, vector<int>(n + 1, 0));
        for(auto& e : pairs){
            int a = e[0], b = e[1], i = 0, j = 0; f[a][b] = f[b][a] = 1;
            while(i < preferences[a].size() && preferences[a][i] != b)f[a][preferences[a][i++]] = 2; 
            while(j < preferences[b].size() && preferences[b][j] != a)f[b][preferences[b][j++]] = 2; 
        }
        int ans = 0;
        for(int i = 0; i < n; ++i)
            for(int j = 0; j < n; ++j)
                if(f[i][j] == 2 && f[j][i] == 2){
                    ans += 1;
                    break;
                }
        return ans;
    }
};

LC1583-统计不开心的朋友

原文：https://www.cnblogs.com/Ivessas/p/15141786.html