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  1. #include <bits/stdc++.h>
  2. using namespace std;
  3. int n,x;
  4. int main(){
  5. 	cin >> n >> x;
  6. 	int count = 0;
  7. 	int A[n];
  8. 	map<int,int> num;
  9. 	for (int i = 0; i < n; i++){
  10. 		cin >> A[i];
  11. 		num[A[i]]++;
  12. 	}
  13. 	for (auto i:num){
  14. 		int n = i.first;
  15. 		int m = x - n;
  16. 		cout << m << " " << n << "-" << num[m] << " " << num[n] << endl;
  17. 		if (m > n){
  18. 			count += num[n] * num[m];
  19. 		}
  20. 		if (m == n){
  21. 			count += num[n] * (num[n] - 1) / 2;
  22. 		}
  23. 	}
  24. 	cout << count;
  25. }
Success #stdin #stdout 0.01s 5312KB
comments (?)
stdin
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10 0
0 1 1 1 1 1 1 0 1 1
stdout
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0 0-2 2
-1 1-0 8
1
https://ideone.com/ZQ5okd
language:
C++14 (gcc 8.3)
created:
5 days ago
visibility:
public

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