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  1. #include <bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int tc;
  5. int N, A[200005];
  6. int lol[200005][2];
  7. map<int, int> cnt;
  8. bool yes;
  9.  
  10. int main() {
  11. 	scanf("%d", &tc);
  12. 	while(tc--) {
  13. 		scanf("%d", &N);
  14. 		int mx = 0;
  15. 		for(int i = 1; i <= N; i++) {
  16. 			scanf("%d", &A[i]);
  17. 		}
  18. 		for(int i = 1; i <= N; i++) {
  19. 			if(!cnt.count(A[i])) {
  20. 				cnt[A[i]] = 1;
  21. 				mx = max(A[i], mx);
  22. 				if(mx == i) lol[i][0] = 1;
  23. 			}else break;
  24. 		}
  25. 		cnt.clear();
  26. 		mx = 0;
  27. 		for(int i = N; i > 0; i--) {
  28. 			if(!cnt.count(A[i])) {
  29. 				cnt[A[i]] = 1;
  30. 				mx = max(A[i], mx);
  31. 				if(mx == N - i + 1) lol[i][1] = 1; 
  32. 			}else break;
  33. 		}
  34. 		cnt.clear();
  35. 		int ans = 0;
  36. 		for(int i = 2; i <= N; i++) {
  37. 			if(lol[i - 1][0] && lol[i][1]) {
  38. 				ans++;
  39. 			}
  40. 		}
  41. 		cout << ans << "\n";
  42. 		for(int i = 2; i <= N; i++) {
  43. 			if(lol[i - 1][0] && lol[i][1]) {
  44. 				cout << i - 1 << " " << N - i + 1 << "\n";
  45. 			}
  46. 			lol[i - 1][0] = 0;
  47. 			lol[i - 1][1] = 0;
  48. 			lol[i][1] = 0;
  49. 		}
  50. 		lol[N][0] = 0;
  51. 	}
  52. 	return 0;
  53. }
Success #stdin #stdout 0s 4528KB
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https://ideone.com/VSbVGb
language:
C++14 (gcc 8.3)
created:
4 years ago
visibility:
public

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