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  1. #include <bits/stdc++.h>
  2. using namespace std;
  3.  
  4. const int oo = 2e5 + 2;
  5. const int max_r = 1e9;
  6.  
  7. int n, x;
  8. int a[oo];
  9.  
  10. bool check(int mid) {
  11. 	bool bad[oo];
  12.  
  13. 	for (int i = 1; i <= n; i++) {
  14. 		bool l = 0;
  15. 		if (i > 1 && a[i] - a[i - 1] <= mid) {
  16. 			l = 1;
  17. 		}
  18.  
  19. 		bool r = 0;
  20. 		if (i < n && a[i + 1] - a[i] <= mid) {
  21. 			r = 1;
  22. 		}
  23.  
  24. 		bad[i] = (!l && !r);
  25. 	}
  26.  
  27. 	int cnt = 0;
  28. 	for (int i = 1; i <= n; i++) {
  29. 		if (bad[i] == 0) {
  30. 			continue;
  31. 		}
  32.  
  33. 		cnt++;
  34.  
  35. 		if (i < n && bad[i + 1] && a[i + 1] - a[i] <= 2 * mid) {
  36. 			i++;
  37. 		}
  38. 	}
  39.  
  40. 	return cnt <= x;
  41. }
  42.  
  43. void solve() {
  44. 	cin >> n >> x;
  45. 	for (int i = 1; i <= n; i++) {
  46. 		cin >> a[i];
  47. 	}
  48.  
  49. 	int res = max_r;
  50. 	int l = 1, r = max_r;
  51. 	while (l <= r) {
  52. 		int mid = l + (r - l) / 2;
  53. 		if (check(mid)) {
  54. 			res = min(res, mid);
  55. 			r = mid - 1;
  56. 		} else {
  57. 			l = mid + 1;
  58. 		}
  59. 	}
  60.  
  61. 	cout << res <<'\n';
  62. }
  63.  
  64. int main() {
  65.  
  66. 	int t;
  67. 	cin >> t;
  68. 	while(t--) {
  69. 		solve();
  70. 	}
  71.  
  72. 	return 0;
  73. }
Success #stdin #stdout 0.01s 5344KB
comments (?)
stdin
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4
2 0
1 3
2 1
1 3
3 1
2 5 7
10 2
0 6 8 10 13 14 16 19 25 31
stdout
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2
1
2
3
https://ideone.com/UUb3WU
language:
C++ (gcc 8.3)
created:
1 day ago
visibility:
public

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