oj.uz

Submission #798815

# Submission time Handle Problem Language Result Execution time Memory
798815 2023-07-31T04:39:09 Z arush_agu Watching (JOI13_watching) C++17
100 / 100
 429 ms 30348 KB 
#include <algorithm>
#include <cctype>
#include <cmath>
#include <cstdio>
#include <cstring>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <functional>
#include <iomanip>
#include <iostream>
#include <iterator>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <vector>

#ifdef DEBUG
#include <time.h>
#endif

#define all(a) (a).begin(), (a).end()
#define rev(a) (a).rbegin(), (a).rend()
#define F first
#define S second
int recur_depth = 0;
#ifdef DEBUG
#define dbg(x)                                                                 \
  {                                                                            \
    ++recur_depth;                                                             \
    auto x_ = x;                                                               \
    --recur_depth;                                                             \
    cerr << string(recur_depth, '\t') << "\e[91m" << __func__ << ":"           \
         << __LINE__ << "\t" << #x << " = " << x_ << "\e[39m" << endl;         \
  }
#else
#define dbg(x)
#endif

using namespace std;
using namespace __gnu_pbds;

typedef pair<int, int> ii;

typedef long long ll;
typedef long double ld;
typedef pair<ll, ll> llll;

typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<pair<int, int>> vii;
typedef vector<vii> vvii;

typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<pair<ll, ll>> vll;
typedef vector<vll> vvll;

typedef vector<bool> vb;

template <class type1>
using ordered_set = tree<type1, null_type, less<type1>, rb_tree_tag,
                         tree_order_statistics_node_update>;

template <typename A, typename B>
ostream &operator<<(ostream &os, const pair<A, B> &p) {
  return os << '(' << p.first << ", " << p.second << ')';
}
template <typename T_container, typename T = typename enable_if<
                                    !is_same<T_container, string>::value,
                                    typename T_container::value_type>::type>
ostream &operator<<(ostream &os, const T_container &v) {
  os << '{';
  string sep;
  for (const T &x : v)
    os << sep << x, sep = ", ";
  return os << '}';
}

const ll MOD = 1e9 + 7;
// const ll MOD = 998244353;
const ll INF = 1e18;
const ld EPS = 1e-9;

void solve() {
  int n, p, q;
  cin >> n >> p >> q;
  vl a(n);
  for (ll &x : a)
    cin >> x;

  if (p + q >= n) {
    cout << "1\n";
    return;
  }

  sort(all(a));

  auto check = [&](ll w) -> bool {
    vi cw(n), cw2(n);
    int w_idx = 0, w2_idx = 0;
    for (int i = 0; i < n; i++) {
      while (a[w_idx] <= a[i] - w)
        w_idx++;
      while (a[w2_idx] <= a[i] - w - w)
        w2_idx++;

      cw[i] = w_idx, cw2[i] = w2_idx;
    }

    vvl dp(n + 1, vl(q + 1));
    for (int i = 1; i <= n; i++) {
      int idx = i - 1;
      dp[i][0] = dp[cw[idx]][0] + 1;
      for (int qq = 1; qq <= q; qq++) {
        dp[i][qq] = min(dp[cw2[idx]][qq - 1], dp[cw[idx]][qq] + 1);
      }

      if (dp[i][q] > p)
        return 0;
    }

    return dp[n][q] <= p;
  };

  int l = 1, r = 1e9, ans = 1e9;
  while (l <= r) {
    int mid = (l + r) / 2;
    if (check(mid)) {
      r = mid - 1;
      ans = mid;
    } else
      l = mid + 1;
  }

  cout << ans << "\n";
}

int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(NULL);

  clock_t start = clock();

  int test_cases = 1;
  // cin >> test_cases;

  while (test_cases--)
    solve();

#ifdef DEBUG
  cerr << fixed << setprecision(10)
       << "\nTime Taken: " << (double)(clock() - start) / CLOCKS_PER_SEC
       << "s\n";
#endif
  return 0;
}

Compilation message

watching.cpp: In function 'int main()':
watching.cpp:150:11: warning: unused variable 'start' [-Wunused-variable]
  150 |   clock_t start = clock();
      |           ^~~~~

Subtask #1
50.0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 320 KB Output is correct
2 Correct 0 ms 320 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 1 ms 212 KB Output is correct
7 Correct 1 ms 320 KB Output is correct
8 Correct 1 ms 212 KB Output is correct
9 Correct 1 ms 320 KB Output is correct
10 Correct 1 ms 340 KB Output is correct
11 Correct 1 ms 212 KB Output is correct
12 Correct 1 ms 340 KB Output is correct
13 Correct 1 ms 212 KB Output is correct
14 Correct 1 ms 212 KB Output is correct
15 Correct 1 ms 212 KB Output is correct

Subtask #2
50.0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 456 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 1 ms 356 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 1 ms 340 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 4 ms 596 KB Output is correct
8 Correct 159 ms 12396 KB Output is correct
9 Correct 21 ms 2380 KB Output is correct
10 Correct 16 ms 1916 KB Output is correct
11 Correct 429 ms 30348 KB Output is correct
12 Correct 204 ms 15912 KB Output is correct
13 Correct 5 ms 852 KB Output is correct
14 Correct 3 ms 588 KB Output is correct
15 Correct 5 ms 692 KB Output is correct