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  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. #define scan(a) scanf("%d",&a)
  5. #define r5 100005
  6. #define f(i,a,b) for(i=a;i<b;i++)
  7. #define print(a) printf("%d\n",a)
  8. #define pb push_back
  9. #define nl printf("\n");
  10. #define inf INT_MAX
  11. typedef long long int lli;
  12. typedef pair<int,int> ii;
  13.  
  14. bool visited[r5];
  15. vector<int> adj[r5];
  16.  
  17. void dfs(int v){
  18. 	visited[v]=true;
  19. 	vector<int>::iterator it;
  20. 	for(it=adj[v].begin();it!=adj[v].end();it++){
  21. 		if(!visited[*it])
  22. 		dfs(*it);
  23. 	}
  24. }
  25.  
  26. int main(){
  27. 	int t;
  28. 	scan(t);
  29. 	while(t--){
  30. 		int i,n,m;
  31. 		f(i,0,r5){
  32. 			adj[i].clear();
  33. 			visited[i]=false;
  34. 		}
  35. 		scan(n);
  36. 		scan(m);
  37. 		int x,y;
  38. 		f(i,0,m){
  39. 			scan(x);
  40. 			scan(y);
  41. 			adj[x].push_back(y);
  42. 			adj[y].push_back(x);
  43. 		}
  44. 		int ans=0;
  45. 		f(i,1,n+1){
  46. 			if(!visited[i]){
  47. 				ans++;
  48. 				dfs(i);
  49. 			}
  50. 		}
  51. 		print(ans);
  52. 	}
  53. 	return 0;
  54. }
Success #stdin #stdout 0s 4544KB
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https://ideone.com/pLTs1B
language:
C++ (gcc 8.3)
created:
8 years ago
visibility:
public

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