fork download 
  1. #include <bits/stdc++.h>
  2.  
  3. using namespace std;
  4.  
  5. #define ll long long
  6. #define ull unsigned long long
  7. #define initial first
  8. #define added second
  9. #define sort_all(v) sort(v.begin(), v.end())
  10.  
  11. #define EGRY                          \
  12.     ios_base::sync_with_stdio(false); \
  13.     cin.tie(NULL);
  14.  
  15. const int MAX = 6400000;
  16. const int MOD = 998244353;
  17. const ll OO = LLONG_MAX;
  18. const double EPS = (double)1e-9;
  19.  
  20. const int N = 6e3 + 10;
  21.  
  22. struct SparseTable
  23. {
  24.     int n, log_table[N];
  25.     pair<int, int> sparse_table[N][15];
  26.  
  27.     void build(const vector<int> &heights)
  28.     {
  29.         n = heights.size();
  30.         for (int i = 0; i < n; ++i)
  31.         {
  32.             sparse_table[i][0] = {heights[i], i};
  33.         }
  34.  
  35.         for (int i = 2; i < N; ++i)
  36.         {
  37.             log_table[i] = log_table[i / 2] + 1;
  38.         }
  39.  
  40.         for (int size = 1; size <= log_table[n]; ++size)
  41.         {
  42.             for (int i = 0; i + (1 << size) <= n; ++i)
  43.             {
  44.                 sparse_table[i][size] = min(sparse_table[i][size - 1], sparse_table[i + (1 << (size - 1))][size - 1]);
  45.             }
  46.         }
  47.     }
  48.  
  49.     pair<int, int> query(int left, int right)
  50.     {
  51.         int length = right - left + 1;
  52.         int log_value = log_table[length];
  53.         return min(sparse_table[left][log_value], sparse_table[right - (1 << log_value) + 1][log_value]);
  54.     }
  55. };
  56.  
  57. int min_brush_strokes(SparseTable &st, int left, int right, int base, const vector<int> &heights)
  58. {
  59.     if (left > right)
  60.     {
  61.         return 0;
  62.     }
  63.  
  64.     auto [min_value, min_index] = st.query(left, right);
  65.  
  66.     int left_strokes = min_brush_strokes(st, left, min_index - 1, min_value, heights);
  67.  
  68.     int right_strokes = min_brush_strokes(st, min_index + 1, right, min_value, heights);
  69.  
  70.     int strokes_from_current_min = left_strokes + right_strokes + (min_value - base);
  71.  
  72.     return min(strokes_from_current_min, right - left + 1);
  73. }
  74.  
  75. void solve()
  76. {
  77.     int n;
  78.     cin >> n;
  79.     vector<int> heights(n);
  80.     for (int i = 0; i < n; ++i)
  81.     {
  82.         cin >> heights[i];
  83.     }
  84.  
  85.     SparseTable st;
  86.     st.build(heights);
  87.  
  88.     cout << min_brush_strokes(st, 0, n - 1, 0, heights);
  89. }
  90.  
  91. int main()
  92. {
  93.     EGRY int t = 1;
  94.     cin >> t;
  95.     while (t--)
  96.     {
  97.         solve();
  98.         cout << endl;
  99.     }
  100.     return 0;
  101. }
Success #stdin #stdout 0.01s 5288KB
comments (?)
stdin 
Standard input is empty
stdout 
0
https://ideone.com/x8kZWf
language:
C++14 (gcc 8.3)
created:
280 days 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!