Number of Provinces

There are n cities. Some of them are connected, while some are not. If city a is connected directly with city b, and city b is connected directly with city c, then city a is connected indirectly with city c.

A province is a group of directly or indirectly connected cities and no other cities outside of the group.

You are given an n x n matrix isConnected where isConnected[i][j] = 1 if the ith city and the jth city are directly connected, and isConnected[i][j] = 0 otherwise.

Return the total number of provinces.

Example 1:

Input: isConnected = [[1,1,0],[1,1,0],[0,0,1]]
Output: 2

Example 2:

Input: isConnected = [[1,0,0],[0,1,0],[0,0,1]]
Output: 3

Constraints:

• 1 <= n <= 200

• n == isConnected.length

• n == isConnected[i].length

• isConnected[i][j] is 1 or 0.

• isConnected[i][i] == 1

• isConnected[i][j] == isConnected[j][i]

public class Solution {
    public int FindCircleNum(int[][] isConnected)
    {
        int num = 0;    
        bool[] visited=new bool[isConnected.Length];
        for (int i = 0; i < isConnected.Length; i++)
        {
            if (!visited[i])
            {
                FindCircleNum(isConnected, visited, i);
                num++;
            }
        }
        return num; 
    }
    public void FindCircleNum(int[][] isConnected, bool[] visited, int index)
    {
        if (visited[index])
        {
            return;
        }
        visited[index] = true;
        for (int j = 0; j < isConnected[index].Length; j++)
        {
            if (!visited[j] && isConnected[index][j] == 1)
            {
                FindCircleNum(isConnected, visited, j);
            }

        }
    }
}