oj.uz

Submission #392678

# Submission time Handle Problem Language Result Execution time Memory
392678 2021-04-21T13:29:42 Z usachevd0 Shortcut (IOI16_shortcut) C++17
0 / 100
 1 ms 588 KB 
#pragma gcc optimize("Ofast")
//#pragma gcc optimize("O3")
//#pragma gcc optimize("no-stack-protector")
//#pragma gcc optimize("unroll-loops")
#pragma gcc target("avx,avx2,ffa")
#include <bits/stdc++.h>
#ifndef DEBUG
  #include "shortcut.h"
#endif

using namespace std;

#define fi first
#define se second
#define mp make_pair
#define pb push_back
#define all(a) (a).begin(), (a).end()
using ll = long long;
using ull = unsigned long long;
using pii = pair<int, int>;
using pil = pair<int, ll>;
using pli = pair<ll, int>;
using pll = pair<ll, ll>;
using ld = long double;
/*template<typename T1, typename T2> bool chkmin(T1& x, T2 y) {
  return y < x ? (x = y, true) : false;
}
template<typename T1, typename T2> bool chkmax(T1& x, T2 y) {
  return y > x ? (x = y, true) : false;
}*/
void chkmin(ll& x, ll y) {
  if (y < x) {
    x = y;
  }
}
void chkmax(ll& x, ll y) {
  if (y > x) {
    x = y;
  }
}
void debug_out() {
  cerr << endl;
}
template<typename T1, typename... T2> void debug_out(T1 A, T2... B) {
  cerr << ' ' << A;
  debug_out(B...);
}
template<typename T> void mdebug_out(T* a, int n) {
  for (int i = 0; i < n; ++i) {
    cerr << a[i] << ' ';
  }
  cerr << endl;
}
#ifdef DEBUG
  #define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
  #define mdebug(a, n) cerr << #a << ": ", mdebug_out(a, n)
#else
  #define debug(...) 1337
  #define mdebug(a, n) 1337
#endif
template<typename T> ostream& operator << (ostream& stream, const vector<T>& v) {
  for (auto& x : v) {
    stream << x << ' ';
  }
  return stream;
}
template<typename T1, typename T2> ostream& operator << (ostream& stream, const pair<T1, T2>& p) {
  return stream << p.first << ' ' << p.second;
}


const ll inf64 = 1e18;

const int maxN = 3003;

int n, c;
ll sum_lo[maxN][maxN], sum_hi[maxN][maxN];
ll dif_lo[maxN][maxN], dif_hi[maxN][maxN];
ll sum_lo_f[maxN][maxN], sum_hi_f[maxN][maxN];
ll dif_lo_f[maxN][maxN], dif_hi_f[maxN][maxN];
ll naive[maxN][maxN];
ll x[maxN], d[maxN];

ll find_shortcut(int _n, vector<int> dx, vector<int> _d, int _c) {
  n = _n;
  c = _c;
  for (int i = 0; i < n; ++i) d[i] = _d[i];
  for (int i = 0; i + 1 < n; ++i) {
    x[i + 1] = x[i] + dx[i];
  }

  int maxd1 = -1e9, maxd2 = -1e9;
  for (int i = 0; i < n; ++i) {
    if (d[i] >= maxd1) {
      maxd2 = maxd1;
      maxd1 = d[i];
    } else if (d[i] > maxd2) {
      maxd2 = d[i];
    }
  }

  for (int i = 0; i < n; ++i) {
    for (int j = i + 1; j < n; ++j) {
      naive[i][j] = d[i] + d[j] + x[j] - x[i];
      sum_lo_f[i][j] = x[i] + x[j] + d[i] + d[j] + c;
      sum_hi_f[i][j] = x[i] + x[j] - d[i] - d[j] - c;
      dif_lo_f[i][j] = d[i] + d[j] + c - x[i] + x[j];
      dif_hi_f[i][j] = -d[i] - d[j] - c + x[j] - x[i];
    }
  }
  for (int i = 0; i <= n; ++i) {
    fill(sum_lo[i], sum_lo[i] + n + 1, -inf64);
    fill(sum_hi[i], sum_hi[i] + n + 1, +inf64);
    fill(dif_lo[i], dif_lo[i] + n + 1, -inf64);
    fill(dif_hi[i], dif_hi[i] + n + 1, +inf64);
  }

  auto good = [&](ll D) -> bool {
    for (int i = 0; i < n; ++i) {
      for (int j = i + 1; j < n; ++j) {
        if (naive[i][j] > D) {
          ll T = D - d[i] - d[j] - c;
          if (T < 0) {
            return false;
          }
          sum_lo[i][j] = sum_lo_f[i][j] - D;
          sum_hi[i][j] = sum_hi_f[i][j] + D;
          dif_lo[i][j] = dif_lo_f[i][j] - D;
          dif_hi[i][j] = dif_hi_f[i][j] + D;
        } else {
          sum_lo[i][j] = -inf64;
          sum_hi[i][j] = +inf64;
          dif_lo[i][j] = -inf64;
          dif_hi[i][j] = +inf64;
        }
      }
    }

    for (int i = 0; i < n; ++i) {
      ll cur = -inf64;
      for (int j = n - 1; j >= i; --j) {
        chkmax(cur, sum_lo[i][j]);
        sum_lo[i][j] = cur;
      }
      cur = +inf64;
      for (int j = i + 1; j < n; ++j) {
        chkmin(cur, sum_hi[i][j]);
        sum_hi[i][j] = cur;
      }
      cur = -inf64;
      for (int j = n - 1; j >= i; --j) {
        chkmax(cur, dif_lo[i][j]);
        dif_lo[i][j] = cur;
      }
      cur = +inf64;
      for (int j = i + 1; j < n; ++j) {
        chkmin(cur, dif_hi[i][j]);
        dif_hi[i][j] = cur;
      }
    }
    for (int j = 0; j < n; ++j) {
      ll cur = -inf64;
      for (int i = j - 1; i >= 0; --i) {
        chkmax(cur, sum_lo[i][j]);
        sum_lo[i][j] = cur;
      }
      cur = +inf64;
      for (int i = 0; i < j; ++i) {
        chkmin(cur, sum_hi[i][j]);
        sum_hi[i][j] = cur;
      }
      cur = -inf64;
      for (int i = 0; i < j; ++i) {
        chkmax(cur, dif_lo[i][j]);
        dif_lo[i][j] = cur;
      }
      cur = +inf64;
      for (int i = j - 1; i >= 0; --i) {
        chkmin(cur, dif_hi[i][j]);
        dif_hi[i][j] = cur;
      }
    }

    /*for (int i = n - 1; i >= 0; --i) {
      for (int j = n - 1; j > i; --j) {
        chkmax(sum_lo[i][j], sum_lo[i + 1][j]);
        chkmax(sum_lo[i][j], sum_lo[i][j + 1]);
      }
    }
    for (int i = 0; i < n; ++i) {
      for (int j = n - 1; j > i; --j) {
        if (i > 0) chkmax(dif_lo[i][j], dif_lo[i - 1][j]);
        chkmax(dif_lo[i][j], dif_lo[i][j + 1]);
      }
    }
    for (int i = n - 1; i >= 0; --i) {
      for (int j = i + 1; j < n; ++j) {
        chkmin(dif_hi[i][j], dif_hi[i + 1][j]);
        if (j > 0) chkmin(dif_hi[i][j], dif_hi[i][j - 1]);
      }
    }*/
    for (int l = 0; l < n; ++l) {
      for (int r = l + 1; r < n; ++r) {
        ll sum = x[l] + x[r];
        ll dif = x[r] - x[l];
        /*if (l == 1 && r == 3) {
          debug(sum, dif);
          debug(sum_lo[l][r], sum_hi[l][r]);
          debug(dif_lo[l][r], dif_hi[l][r]);
        }*/
        if (sum_lo[l][r] <= sum && sum <= sum_hi[l][r] &&
            dif_lo[l][r] <= dif && dif <= dif_hi[l][r])
        {
          return true;
        }
      }
    }
    return false;
  };

  ll vl = maxd1 + maxd2;
  ll vr = maxd1 + maxd2 + x[n - 1];
  while (vr - vl > 1) {
    ll vm = (vl + vr) >> 1;
    if (good(vm)) {
      vr = vm;
    } else {
      vl = vm;
    }
  }
  return vr;
}


#ifdef DEBUG
int32_t main() {
#ifdef DEBUG
  freopen("in", "r", stdin);
#endif
  ios::sync_with_stdio(0);
  cin.tie(0);

  int n, c;
  cin >> n >> c;
  vector<int> l(n - 1), d(n);
  for (int& x : l) cin >> x;
  for (int& x : d) cin >> x;
  cout << find_shortcut(n, l, d, c) << '\n';

  return 0;
}
#endif

Compilation message

shortcut.cpp:1: warning: ignoring #pragma gcc optimize [-Wunknown-pragmas]
    1 | #pragma gcc optimize("Ofast")
      | 
shortcut.cpp:5: warning: ignoring #pragma gcc target [-Wunknown-pragmas]
    5 | #pragma gcc target("avx,avx2,ffa")
      |

Subtask #1
0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 460 KB n = 4, 80 is a correct answer
2 Correct 1 ms 588 KB n = 9, 110 is a correct answer
3 Correct 1 ms 460 KB n = 4, 21 is a correct answer
4 Correct 1 ms 332 KB n = 3, 4 is a correct answer
5 Correct 1 ms 332 KB n = 2, 62 is a correct answer
6 Correct 1 ms 332 KB n = 2, 3 is a correct answer
7 Incorrect 1 ms 332 KB n = 3, incorrect answer: jury 29 vs contestant 20
8 Halted 0 ms 0 KB -

Subtask #2
0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 460 KB n = 4, 80 is a correct answer
2 Correct 1 ms 588 KB n = 9, 110 is a correct answer
3 Correct 1 ms 460 KB n = 4, 21 is a correct answer
4 Correct 1 ms 332 KB n = 3, 4 is a correct answer
5 Correct 1 ms 332 KB n = 2, 62 is a correct answer
6 Correct 1 ms 332 KB n = 2, 3 is a correct answer
7 Incorrect 1 ms 332 KB n = 3, incorrect answer: jury 29 vs contestant 20
8 Halted 0 ms 0 KB -

Subtask #3
0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 460 KB n = 4, 80 is a correct answer
2 Correct 1 ms 588 KB n = 9, 110 is a correct answer
3 Correct 1 ms 460 KB n = 4, 21 is a correct answer
4 Correct 1 ms 332 KB n = 3, 4 is a correct answer
5 Correct 1 ms 332 KB n = 2, 62 is a correct answer
6 Correct 1 ms 332 KB n = 2, 3 is a correct answer
7 Incorrect 1 ms 332 KB n = 3, incorrect answer: jury 29 vs contestant 20
8 Halted 0 ms 0 KB -

Subtask #4
0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 460 KB n = 4, 80 is a correct answer
2 Correct 1 ms 588 KB n = 9, 110 is a correct answer
3 Correct 1 ms 460 KB n = 4, 21 is a correct answer
4 Correct 1 ms 332 KB n = 3, 4 is a correct answer
5 Correct 1 ms 332 KB n = 2, 62 is a correct answer
6 Correct 1 ms 332 KB n = 2, 3 is a correct answer
7 Incorrect 1 ms 332 KB n = 3, incorrect answer: jury 29 vs contestant 20
8 Halted 0 ms 0 KB -

Subtask #5
0 / 33.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 460 KB n = 4, 80 is a correct answer
2 Correct 1 ms 588 KB n = 9, 110 is a correct answer
3 Correct 1 ms 460 KB n = 4, 21 is a correct answer
4 Correct 1 ms 332 KB n = 3, 4 is a correct answer
5 Correct 1 ms 332 KB n = 2, 62 is a correct answer
6 Correct 1 ms 332 KB n = 2, 3 is a correct answer
7 Incorrect 1 ms 332 KB n = 3, incorrect answer: jury 29 vs contestant 20
8 Halted 0 ms 0 KB -

Subtask #6
0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 460 KB n = 4, 80 is a correct answer
2 Correct 1 ms 588 KB n = 9, 110 is a correct answer
3 Correct 1 ms 460 KB n = 4, 21 is a correct answer
4 Correct 1 ms 332 KB n = 3, 4 is a correct answer
5 Correct 1 ms 332 KB n = 2, 62 is a correct answer
6 Correct 1 ms 332 KB n = 2, 3 is a correct answer
7 Incorrect 1 ms 332 KB n = 3, incorrect answer: jury 29 vs contestant 20
8 Halted 0 ms 0 KB -

Subtask #7
0 / 4.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 460 KB n = 4, 80 is a correct answer
2 Correct 1 ms 588 KB n = 9, 110 is a correct answer
3 Correct 1 ms 460 KB n = 4, 21 is a correct answer
4 Correct 1 ms 332 KB n = 3, 4 is a correct answer
5 Correct 1 ms 332 KB n = 2, 62 is a correct answer
6 Correct 1 ms 332 KB n = 2, 3 is a correct answer
7 Incorrect 1 ms 332 KB n = 3, incorrect answer: jury 29 vs contestant 20
8 Halted 0 ms 0 KB -

Subtask #8
0 / 3.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 460 KB n = 4, 80 is a correct answer
2 Correct 1 ms 588 KB n = 9, 110 is a correct answer
3 Correct 1 ms 460 KB n = 4, 21 is a correct answer
4 Correct 1 ms 332 KB n = 3, 4 is a correct answer
5 Correct 1 ms 332 KB n = 2, 62 is a correct answer
6 Correct 1 ms 332 KB n = 2, 3 is a correct answer
7 Incorrect 1 ms 332 KB n = 3, incorrect answer: jury 29 vs contestant 20
8 Halted 0 ms 0 KB -