Codeforces Round #254 (Div. 2) 445B. DZY Loves Chemistry Solution

   Problem Link:  https://codeforces.com/problemset/problem/445/B

Solution in C++:

1. /// La ilaha illellahu muhammadur rasulullah
2. ///******Bismillahir-Rahmanir-Rahim******///
3. /// Abul Hasnat Tonmoy
4. /// Department of CSE,23rd batch
5. /// Islamic University,Bangladesh
6. ///**********ALLAH IS ALMIGHTY************///
7. #include <bits/stdc++.h>
8. using namespace std;
9. vector< long long> vec[100000];
10. bool visited[100000];
11. void dfs(int source) {
12. visited[source] = 1;
13. for (int i = 0; i < vec[source].size(); i++) {
14. int next = vec[source][i];
15. if (visited[next] == 0) dfs(next);
16. }
17. }
18. int main() {
19. long long ans,nodes, edges, cnt = 0;
20. cin >> nodes >> edges;
21. for (int i = 0; i < edges; i++) {
22. long long u, v;
23. cin >> u >> v;
24. vec[u].push_back(v);
25. vec[v].push_back(u);
26. }
27. for (int i = 1; i <= nodes; i++) {
28. if (visited[i] == 0) {
29. cnt++;
30. dfs(i);
31. }
32. }
33. ans=pow(2, nodes - cnt) ;
34. cout << ans << endl;
35. return 0;
36. }