Submission #1245256

#	Time	Username	Problem	Language	Result	Execution time	Memory
1245256		duyanhloveav	K blocks (IZhO14_blocks)	C++20	100 / 100	116 ms	40876 KiB

blocks

#include <bits/stdc++.h>
using namespace std;

#define MASK(i) (1LL << (i))
#define BIT(x, i) (((x) >> (i)) & 1LL)

using ll = long long;

const int mxn = 9 + 1e6;
const int inf = 0x3f3f3f3f;
const ll lnf = 0x3f3f3f3f3f3f3f3f;

void _27augain(void) {
  int n, k;
  cin >> n >> k;
  vector<int> a(n + 1);
  vector<vector<int>> dp(k + 1, vector<int>(n + 1, inf));
  for (int i = 1, m = 0; i <= n; ++i) {
    cin >> a[i];
    dp[1][i] = m = max(m, a[i]);
  }
  for (int i = 2; i <= k; ++i) {
    deque<array<int, 2>> q;
    for (int j = 1; j <= n; ++j) {
      int v = dp[i - 1][j - 1];
      while (!q.empty() && q.back()[0] < a[j]) {
        v = min(v, q.back()[1]);
        q.pop_back();
      }
      if (q.empty() || v + a[j] < q.back()[0] + q.back()[1]) {
        q.push_back({a[j], v});
      }
      dp[i][j] = j >= i ? q.back()[0] + q.back()[1] : inf;
    }
  }
  cout << dp[k][n] << "\n";
}

int32_t main(void) {
#define task "27augain"
  cin.tie(0)->sync_with_stdio(0);
  for (string iext : {"in", "inp"}) {
    if (fopen((task "." + iext).c_str(), "r")) {
      freopen((task "." + iext).c_str(), "r", stdin);
      freopen(task ".out", "w", stdout);
    }
  }
  int testcase = 1;
  // cin >> testcase;
  while (testcase--) {
    _27augain();
  }
  return 0;
}

Compilation message (stderr)

blocks.cpp: In function 'int32_t main()':
blocks.cpp:44:14: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   44 |       freopen((task "." + iext).c_str(), "r", stdin);
      |       ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
blocks.cpp:45:14: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   45 |       freopen(task ".out", "w", stdout);
      |       ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 14 / 14
• Subtask 2: 18 / 18
• Subtask 3: 21 / 21
• Subtask 4: 47 / 47