技術標籤：演算法題leetcode演算法

class Solution {
public:
    int findCircleNum(vector<vector<int>>& isConnected) {
        if(isConnected.size() == 0 ||isConnected[0].size() == 0)return 0;
        vector<int> flag(isConnected.size(),1);
        int n = isConnected.size();
        int num = 0;
        for(int i = 0;i < n;i++)//row:i
        {
           if(flag[i])
           {
            num++;
            flag[i] = 0;
            for(int j = i + 1;j < n;j++)//column:j
            {
                if(isConnected[i][j] && flag[j])//i connect j
                {
                    //isConnected[i][j] = 0;
                    flag[j] = 0;
                    stack<int> c;
                    c.push(j);//push into stack
                    while(!c.empty())
                    {
                        int ii = c.top();
                        c.pop();
                        for(int jj = 0;jj < n;jj++)
                        {
                            if(isConnected[ii][jj] && flag[jj])
                            {
                                flag[jj] = 0;
                                //isConnected[ii][jj] = 0;
                                c.push(jj);
                            }
                        }
                    }
                }
            }
           } 
        }
        return num;
    }
};