Number of Provinces

Given a graph with V vertices. Find the number of Provinces.
Note: A province is a group of directly or indirectly connected cities and no other cities outside of the group.

• Time : O(v^2logv)
• Space : O(v)

class Solution {
    int uf[500];
    int find(int u) {
        return uf[u] == u ? u : uf[u] = find(uf[u]);
    }
    void uni(int u, int v) {
        int pu = find(u), pv = find(v);
        uf[pu] = uf[pv] = min(pu, pv);
    }
public:
    int numProvinces(vector<vector<int>> adj, int V) {
        for(int i = 0; i < V; i++) uf[i] = i;
        for(int i = 0; i < V; i++) {
            for(int j = i + 1; j < V; j++) {
                if(adj[i][j]) uni(i, j);
            }
        }
        unordered_set<int> us;
        for(int i = 0; i < V; i++)
            us.insert(find(i));
        return us.size();
    }
};