oj.uz

Submission #278252

# Submission time Handle Problem Language Result Execution time Memory
278252 2020-08-21T11:28:27 Z erray Watching (JOI13_watching) C++17
100 / 100
 638 ms 16184 KB 
// author: erray
#include<bits/stdc++.h>
#undef DEBUG 
using namespace std;

template<typename T, typename F> string to_string(pair<T, F> p);
string to_string(string s) {
  return '"' + s + '"';
}
string to_string(char c) {
  return (string) "'" + c + "'";
}
string to_string(const char* p) {
  return to_string((string) p);
}
string to_string(bool B) {
  return (B ? "true" : "false");
}
string to_string(vector<bool> v) {
  string res = "{";
  for (int i = 0; i < (int) v.size(); ++i) {
    if ((int) res.size() > 1) res += ", ";
    res += to_string(v[i]);
  }
  res += "}";
  return res;
}
template<size_t T> string to_string(bitset<T> bs) {
  return bs.to_string();
}
template<typename T> string to_string(T v) {
  string res = "{";
  for (auto& el : v) {
    if ((int) res.size() > 1) res += ", ";
    res += to_string(el);
  }
  res += "}";
  return res;
}
template<typename T, typename F> string to_string(pair<T, F> p) {
  return '(' + to_string(p.first) + ", " + to_string(p.second) + ')';
}
void debug_out() {
  cerr << endl;
}
template<typename Head, typename... Tail> void debug_out(Head H, Tail... T) {
  cerr << " " << to_string(H);
  debug_out(T...);
}
#ifdef DEBUG
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:" , debug_out(__VA_ARGS__)
#else
#define debug(...) (void) 37
#endif
 
int main () {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  int n, p, q;
  cin >> n >> p >> q;
  p = min(p, n);
  vector<int> a(n);
  for (int i = 0; i < n; ++i) cin >> a[i];
  sort(a.begin(), a.end());
  auto check = [&](long long l) {
    vector<vector<int>> dp(n, vector<int>(p + 1, INT_MAX));
    auto get = [&](int x, int y) {
      if (y > p) return (int) 1e9;
      if (x == n) return 0;
      return dp[x][y];
    };
    int p1 = n - 1, p2 = n - 1;
    for (int i = n - 1; i >= 0; --i) {
      while (p1 > 0 && a[p1] >= a[i] + l) --p1;
      while (p2 > 0 && a[p2] >= a[i] + 2 * l) --p2;
      debug(i, p1, p2); 
      for (int j = 0; j <= p; ++j) {
        dp[i][j] = get(p1 + 1, j + 1);
        dp[i][j] = min(dp[i][j], get(p2 + 1, j) + 1);
      }
    }
    debug(dp);
    return dp[0][0] <= q;
  };
  int s = 1, e = (int) 1e9;
  while (s != e) {
    int mid = (s + e) >> 1;
    if (check(mid)) e = mid;
    else s = mid + 1;    
    debug(s, e);
  }          
  cout << s << '\n';
}

Subtask #1
50.0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 384 KB Output is correct
2 Correct 1 ms 384 KB Output is correct
3 Correct 1 ms 384 KB Output is correct
4 Correct 2 ms 384 KB Output is correct
5 Correct 2 ms 384 KB Output is correct
6 Correct 3 ms 392 KB Output is correct
7 Correct 1 ms 384 KB Output is correct
8 Correct 1 ms 384 KB Output is correct
9 Correct 1 ms 512 KB Output is correct
10 Correct 1 ms 384 KB Output is correct
11 Correct 2 ms 384 KB Output is correct
12 Correct 1 ms 384 KB Output is correct
13 Correct 1 ms 384 KB Output is correct
14 Correct 1 ms 384 KB Output is correct
15 Correct 1 ms 384 KB Output is correct

Subtask #2
50.0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 512 KB Output is correct
2 Correct 1 ms 384 KB Output is correct
3 Correct 493 ms 12416 KB Output is correct
4 Correct 637 ms 16184 KB Output is correct
5 Correct 25 ms 1088 KB Output is correct
6 Correct 604 ms 16184 KB Output is correct
7 Correct 7 ms 512 KB Output is correct
8 Correct 37 ms 1456 KB Output is correct
9 Correct 230 ms 6424 KB Output is correct
10 Correct 638 ms 15460 KB Output is correct
11 Correct 28 ms 1268 KB Output is correct
12 Correct 341 ms 8404 KB Output is correct
13 Correct 7 ms 512 KB Output is correct
14 Correct 8 ms 640 KB Output is correct
15 Correct 7 ms 512 KB Output is correct