fork download 
  1. #include <bits/stdc++.h>
  2.  
  3. #define ll long long
  4. #define el cout << '\n'
  5.  
  6. using namespace std;
  7.  
  8. const int maxn = 3e3;
  9. const int maxk = 3e3;
  10. const ll INF = 1e18;
  11.  
  12. int n, k;
  13. ll pre[maxn + 10], dp[maxn + 10][maxk + 10];
  14.  
  15. ll f(int i, int j, int k)
  16. {
  17.     return dp[k][j] + (pre[i] - pre[k]) * (pre[i] - pre[k]); 
  18. }
  19.  
  20. int main()
  21. {
  22.     ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
  23.     if (fopen("SQUARE.INP", "r"))
  24.     {
  25.         freopen("SQUARE.INP", "r", stdin);
  26.         freopen("SQUARE.OUT", "w", stdout);
  27.     }
  28.  
  29.     cin >> n >> k;
  30.     pre[0] = 0;
  31.     for (int i = 1; i <= n; i++)
  32.     {
  33.         ll x;
  34.         cin >> x;
  35.         pre[i] = pre[i - 1] + x;
  36.     }
  37.     for (int i = 1; i <= n; i++)
  38.         for (int j = 0; j <= k; j++)
  39.             dp[i][j] = INF;
  40.     for (int i = 1; i <= n; i++)
  41.         dp[i][1] = pre[i] * pre[i];
  42.     for (int j = 2; j <= k; j++)
  43.     {
  44.         for (int i = 1; i <= n; i++)
  45.         {
  46.             // for (int k = 1; k <= i; k++)
  47.             //     dp[i][j] = min(dp[i][j], f(i, j - 1, k - 1));
  48.             int l = 1, r = i;
  49.             ll ans = 0;
  50.             while (l <= r)
  51.             {
  52.                 int m = l + r >> 1;
  53.                 if (f(i, j - 1, m - 1) <= f(i, j - 1, m))
  54.                 {
  55.                     ans = f(i, j - 1, m - 1);
  56.                     r = m - 1;
  57.                 }
  58.                 else
  59.                 {
  60.                     ans = f(i, j - 1, m);
  61.                     l = m + 1;
  62.                 }
  63.             }
  64.             dp[i][j] = ans;
  65.         }
  66.     }
  67.     cout << dp[n][k];
  68. }
Success #stdin #stdout 0.01s 5280KB
comments (?)
stdin 
Standard input is empty
stdout 
Standard output is empty
https://ideone.com/MkD7Ga
language:
C++14 (gcc 8.3)
created:
9 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!