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  1. #include <bits/stdc++.h>
  2. #define int long long
  3. using namespace std;
  4. const int N = 1e5 + 5;
  5. int pre[N];
  6. int res;
  7.  
  8. bool sorted(int x, int y) {
  9. 	return pre[y] - pre[x - 1] == 0;
  10. }
  11.  
  12. void f(int x, int y) {
  13. 	if (sorted(x, y)) {
  14. 		res = max(res, y - x + 1);
  15. 		return;
  16. 	}
  17. 	if (y == x + 1) {
  18. 		res = max(1LL, res);
  19. 		return;
  20. 	}
  21. 	f(x, (x + y) / 2);
  22. 	f((x + y) / 2 + 1, y);
  23. }
  24.  
  25. signed main() {
  26. 	ios_base::sync_with_stdio(0);
  27. 	cin.tie(0);
  28. 	int n;
  29. 	cin >> n;
  30. 	int a[n + 1];
  31. 	for (int i = 1; i <= n; ++i) cin >> a[i];
  32. 	pre[0] = pre[1] = 0;
  33. 	for (int i = 2; i <= n; ++i) pre[i] = pre[i - 1] + (a[i] < a[i - 1]);
  34. 	f(1, n);
  35. 	cout << res;
  36. 	return 0;
  37. }
Success #stdin #stdout 0s 5320KB
comments (?)
stdin 
8
11 12 1 2 13 14
3 4
stdout 
2
https://ideone.com/5tAraB
language:
C++ (gcc 8.3)
created:
21 hours ago
visibility:
public

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