m0547.py

"""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.

TBD: graph

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]
"""