fork download
copy 
  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. bool check(int k,int arr[],int n){
  4. 	int a[n];
  5. 	for(int i=0;i<n;i++){
  6. 		a[i] = (arr[i]^k);
  7.  
  8. 	}
  9. 	sort(a,a+n);
  10.  
  11. 	for(int i=0;i<n;i++){
  12. 		if(a[i]!=arr[i])
  13. 			return false;
  14. 	}
  15. 	return true;
  16. }
  17. int main(){
  18. 	ios_base::sync_with_stdio(0);
  19. 	cin.tie(0);
  20. 	cout.tie(0);
  21. 	int t;
  22. 	cin>>t;
  23. 	while(t--){
  24. 		int n;
  25. 		cin>>n;
  26. 		int arr[n];
  27. 		for(int i=0;i<n;i++)
  28. 			cin>>arr[i];
  29. 		sort(arr,arr+n);
  30. 		int ans =INT_MAX;
  31. 		int l=1,r=1024;
  32. 		while(l<=r){
  33. 			int mid = l + ((r-l)/2);
  34. 			if(check(mid,arr,n)){
  35. 				ans = min(ans,mid);
  36. 				r=mid-1;
  37. 			}
  38. 			else
  39. 				l=mid+1;
  40.  
  41. 		}
  42. 		if(ans==INT_MAX)
  43. 			cout<<-1<<"\n";
  44. 		else
  45. 			cout<<ans<<"\n";
  46. 	}
  47. }
  48.  
Time limit exceeded #stdin #stdout 5s 4556KB
comments (?)
stdin
copy 
Standard input is empty
stdout
copy 
Standard output is empty
https://ideone.com/q0mqiO
language:
C++ (gcc 8.3)
created:
3 years ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!