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답안 #1008903

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
1008903 2024-06-27T04:59:58 Z nima_aryan Skyscraper (JOI16_skyscraper) C++17
20 / 100
 2000 ms 409880 KB 
/**
 *    author:  NimaAryan
 *    created: 2024-06-26 20:39:48
**/
#include <bits/stdc++.h>

using namespace std;

#ifdef LOCAL
#include "algo/debug.h"
#endif

using i64 = long long;

template <typename T>
T inverse(T a, T m) {
  T u = 0, v = 1;
  while (a != 0) {
    T t = m / a;
    m -= t * a; swap(a, m);
    u -= t * v; swap(u, v);
  }
  assert(m == 1);
  return u;
}

template <typename T>
class Modular {
 public:
  using Type = typename decay<decltype(T::value)>::type;

  constexpr Modular() : value() {}
  template <typename U>
  Modular(const U& x) {
    value = normalize(x);
  }

  template <typename U>
  static Type normalize(const U& x) {
    Type v;
    if (-mod() <= x && x < mod()) v = static_cast<Type>(x);
    else v = static_cast<Type>(x % mod());
    if (v < 0) v += mod();
    return v;
  }

  const Type& operator()() const { return value; }
  template <typename U>
  explicit operator U() const { return static_cast<U>(value); }
  constexpr static Type mod() { return T::value; }

  Modular& operator+=(const Modular& other) { if ((value += other.value) >= mod()) value -= mod(); return *this; }
  Modular& operator-=(const Modular& other) { if ((value -= other.value) < 0) value += mod(); return *this; }
  template <typename U> Modular& operator+=(const U& other) { return *this += Modular(other); }
  template <typename U> Modular& operator-=(const U& other) { return *this -= Modular(other); }
  Modular& operator++() { return *this += 1; }
  Modular& operator--() { return *this -= 1; }
  Modular operator++(int) { Modular result(*this); *this += 1; return result; }
  Modular operator--(int) { Modular result(*this); *this -= 1; return result; }
  Modular operator-() const { return Modular(-value); }

  template <typename U = T>
  typename enable_if<is_same<typename Modular<U>::Type, int>::value, Modular>::type & operator*=(const Modular& rhs) {
#ifdef _WIN32
    uint64_t x = static_cast<int64_t>(value) * static_cast<int64_t>(rhs.value);
    uint32_t xh = static_cast<uint32_t>(x >> 32), xl = static_cast<uint32_t>(x), d, m;
    asm(
      "divl %4; \n\t"
      : "=a" (d), "=d" (m)
      : "d" (xh), "a" (xl), "r" (mod())
    );
    value = m;
#else
    value = normalize(static_cast<int64_t>(value) * static_cast<int64_t>(rhs.value));
#endif
    return *this;
  }
  template <typename U = T>
  typename enable_if<is_same<typename Modular<U>::Type, long long>::value, Modular>::type & operator*=(const Modular& rhs) {
    long long q = static_cast<long long>(static_cast<long double>(value) * rhs.value / mod());
    value = normalize(value * rhs.value - q * mod());
    return *this;
  }
  template <typename U = T>
  typename enable_if < !is_integral<typename Modular<U>::Type>::value, Modular >::type & operator*=(const Modular& rhs) {
    value = normalize(value * rhs.value);
    return *this;
  }

  Modular& operator/=(const Modular& other) { return *this *= Modular(inverse(other.value, mod())); }

  friend const Type& abs(const Modular& x) { return x.value; }

  template <typename U>
  friend bool operator==(const Modular<U>& lhs, const Modular<U>& rhs);

  template <typename U>
  friend bool operator<(const Modular<U>& lhs, const Modular<U>& rhs);

  template <typename V, typename U>
  friend V& operator>>(V& stream, Modular<U>& number);

 private:
  Type value;
};

template <typename T> bool operator==(const Modular<T>& lhs, const Modular<T>& rhs) { return lhs.value == rhs.value; }
template <typename T, typename U> bool operator==(const Modular<T>& lhs, U rhs) { return lhs == Modular<T>(rhs); }
template <typename T, typename U> bool operator==(U lhs, const Modular<T>& rhs) { return Modular<T>(lhs) == rhs; }

template <typename T> bool operator!=(const Modular<T>& lhs, const Modular<T>& rhs) { return !(lhs == rhs); }
template <typename T, typename U> bool operator!=(const Modular<T>& lhs, U rhs) { return !(lhs == rhs); }
template <typename T, typename U> bool operator!=(U lhs, const Modular<T>& rhs) { return !(lhs == rhs); }

template <typename T> bool operator<(const Modular<T>& lhs, const Modular<T>& rhs) { return lhs.value < rhs.value; }

template <typename T> Modular<T> operator+(const Modular<T>& lhs, const Modular<T>& rhs) { return Modular<T>(lhs) += rhs; }
template <typename T, typename U> Modular<T> operator+(const Modular<T>& lhs, U rhs) { return Modular<T>(lhs) += rhs; }
template <typename T, typename U> Modular<T> operator+(U lhs, const Modular<T>& rhs) { return Modular<T>(lhs) += rhs; }

template <typename T> Modular<T> operator-(const Modular<T>& lhs, const Modular<T>& rhs) { return Modular<T>(lhs) -= rhs; }
template <typename T, typename U> Modular<T> operator-(const Modular<T>& lhs, U rhs) { return Modular<T>(lhs) -= rhs; }
template <typename T, typename U> Modular<T> operator-(U lhs, const Modular<T>& rhs) { return Modular<T>(lhs) -= rhs; }

template <typename T> Modular<T> operator*(const Modular<T>& lhs, const Modular<T>& rhs) { return Modular<T>(lhs) *= rhs; }
template <typename T, typename U> Modular<T> operator*(const Modular<T>& lhs, U rhs) { return Modular<T>(lhs) *= rhs; }
template <typename T, typename U> Modular<T> operator*(U lhs, const Modular<T>& rhs) { return Modular<T>(lhs) *= rhs; }

template <typename T> Modular<T> operator/(const Modular<T>& lhs, const Modular<T>& rhs) { return Modular<T>(lhs) /= rhs; }
template <typename T, typename U> Modular<T> operator/(const Modular<T>& lhs, U rhs) { return Modular<T>(lhs) /= rhs; }
template <typename T, typename U> Modular<T> operator/(U lhs, const Modular<T>& rhs) { return Modular<T>(lhs) /= rhs; }

template <typename T, typename U>
Modular<T> power(const Modular<T>& a, const U& b) {
  assert(b >= 0);
  Modular<T> x = a, res = 1;
  U p = b;
  while (p > 0) {
    if (p & 1) res *= x;
    x *= x;
    p >>= 1;
  }
  return res;
}
template <typename T, typename U> Modular<T> operator^(const Modular<T>& lhs, U rhs) { return power(lhs, rhs); };

template <typename T>
bool IsZero(const Modular<T>& number) {
  return number() == 0;
}

template <typename T>
string to_string(const Modular<T>& number) {
  return to_string(number());
}

// U == std::ostream? but done this way because of fastoutput
template <typename U, typename T>
U& operator<<(U& stream, const Modular<T>& number) {
  return stream << number();
}

// U == std::istream? but done this way because of fastinput
template <typename U, typename T>
U& operator>>(U& stream, Modular<T>& number) {
  typename common_type<typename Modular<T>::Type, long long>::type x;
  stream >> x;
  number.value = Modular<T>::normalize(x);
  return stream;
}

/*
using ModType = int;

struct VarMod { static ModType value; };
ModType VarMod::value;
ModType& md = VarMod::value;
using Mint = Modular<VarMod>;
*/

constexpr int md = (int) 1e9 + 7;
using Mint = Modular<std::integral_constant<decay<decltype(md)>::type, md>>;

int main() {
  ios::sync_with_stdio(false);
  cin.tie(nullptr);

  int N, L;
  cin >> N >> L;

  vector<int> A(N);
  for (int i = 0; i < N; ++i) {
    cin >> A[i];
  }

  if (N == 1) {
    cout << 1 << "\n";
    return 0;
  }

  sort(A.begin(), A.end());
  int M = 2 * (N + 5) * 1000;
  int T = M + 1 + L + 5;
  vector f(N + 1, vector(T + 1, vector<Mint>(3)));
  f[1][0][0] = 1;
  f[1][-A[0] + M][1] = 2;
  f[1][2 * -A[0] + M][2] = 1;
  for (int i = 1; i < N; ++i) {
    vector g(N + 1, vector(T + 1, vector<Mint>(3)));
    for (int c = 1; c <= N; ++c) {
      for (int s = 0; s <= T; ++s) {
        {
          if (c + 1 <= N && s - 2 * A[i] >= 0) {
            g[c + 1][s - 2 * A[i]][0] += f[c][s][0] * max(0, c - 1);
          }
          g[c][s][0] += f[c][s][0] * max(0, 2 * c - 2);
          if (c - 1 >= 0 && s + 2 * A[i] <= T) {
            g[c - 1][s + 2 * A[i]][0] += f[c][s][0] * max(0, c - 1);
          }
        }
        {
          if (c + 1 <= N && s - 2 * A[i] >= 0) {
            g[c + 1][s - 2 * A[i]][1] += f[c][s][1] * c;
          }
          if (c + 1 <= N && s - A[i] >= 0) {
            g[c + 1][s - A[i]][0] += f[c][s][1];
          }
          g[c][s][1] += f[c][s][1] * max(0, 2 * c - 1);
          if (s + A[i] <= T) {
            g[c][s + A[i]][0] += f[c][s][1];
          }
          if (c - 1 >= 0 && s + 2 * A[i] <= T) {
            g[c - 1][s + 2 * A[i]][1] += f[c][s][1] * max(0, c - 1);
          }
        }
        {
          if (c + 1 <= N && s - 2 * A[i] >= 0) {
            g[c + 1][s - 2 * A[i]][2] += f[c][s][2] * (c + 1);
          }
          if (c + 1 <= N && s - A[i] >= 0) {
            g[c + 1][s - A[i]][1] += f[c][s][2] * 2;
          }
          g[c][s][2] += f[c][s][2] * 2 * c;
          if (s + A[i] <= T) {
            g[c][s + A[i]][1] += f[c][s][2] * 2;
          }
          if (c - 1 >= 0 && s + 2 * A[i] <= T) {
            g[c - 1][s + 2 * A[i]][2] += f[c][s][2] * max(0, c - 1);
          }
        }
      }
    }
    f.swap(g);
  }

  Mint ans = 0;
  for (int l = 0; l <= L; ++l) {
    ans += f[1][l + M][0];
  }
  cout << ans << "\n";

  return 0;
}

Subtask #1
5.0 / 5.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 6 ms 5644 KB Output is correct
3 Correct 22 ms 8184 KB Output is correct
4 Correct 56 ms 18516 KB Output is correct
5 Correct 145 ms 28436 KB Output is correct
6 Correct 112 ms 28388 KB Output is correct
7 Correct 110 ms 27676 KB Output is correct
8 Correct 132 ms 27604 KB Output is correct
9 Correct 112 ms 28464 KB Output is correct
10 Correct 115 ms 27636 KB Output is correct

Subtask #2
15.0 / 15.0

# 결과 실행 시간 메모리 Grader output
1 Correct 336 ms 50956 KB Output is correct
2 Correct 527 ms 65128 KB Output is correct
3 Correct 490 ms 65128 KB Output is correct
4 Correct 520 ms 65272 KB Output is correct
5 Correct 515 ms 65396 KB Output is correct
6 Correct 473 ms 65120 KB Output is correct
7 Correct 516 ms 65032 KB Output is correct
8 Correct 475 ms 65056 KB Output is correct
9 Correct 471 ms 65116 KB Output is correct
10 Correct 547 ms 65144 KB Output is correct

Subtask #3
0 / 80.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 6 ms 5644 KB Output is correct
3 Correct 22 ms 8184 KB Output is correct
4 Correct 56 ms 18516 KB Output is correct
5 Correct 145 ms 28436 KB Output is correct
6 Correct 112 ms 28388 KB Output is correct
7 Correct 110 ms 27676 KB Output is correct
8 Correct 132 ms 27604 KB Output is correct
9 Correct 112 ms 28464 KB Output is correct
10 Correct 115 ms 27636 KB Output is correct
11 Correct 336 ms 50956 KB Output is correct
12 Correct 527 ms 65128 KB Output is correct
13 Correct 490 ms 65128 KB Output is correct
14 Correct 520 ms 65272 KB Output is correct
15 Correct 515 ms 65396 KB Output is correct
16 Correct 473 ms 65120 KB Output is correct
17 Correct 516 ms 65032 KB Output is correct
18 Correct 475 ms 65056 KB Output is correct
19 Correct 471 ms 65116 KB Output is correct
20 Correct 547 ms 65144 KB Output is correct
21 Execution timed out 2051 ms 409880 KB Time limit exceeded
22 Halted 0 ms 0 KB -