七対子の聴牌確率(巡目別対子数別)

chitoi.cpp

#include <iostream>
#include <iomanip>
#include <iostream>

int main()
{
  constexpr int T_MAX = 18;
  constexpr int T_MIN = 1;
  constexpr int S = 123; // 四麻
  // constexpr int S = 95; // 三麻

  std::array<std::array<double, T_MAX + 1>, 8> table = {};

  for (int t = T_MIN; t <= T_MAX; ++t) {
    table[6][t] = 1.;
  }

  for (int i = 5; i >= 0; --i) {
    for (int t = T_MAX - 1; t >= T_MIN; --t) {
      table[i][t] = (1. - (39. - 6 * i) / (S - t)) * table[i][t + 1] +
                    (39. - 6 * i) / (S - t) * table[i + 1][t + 1];
    }
  }

  std::cout << std::setw(5) << std::left << "Turn";

  for (int i = 6; i >= 0; --i) {
    std::cout << std::setw(12) << std::left << i;
  }

  std::cout << "\n";

  for (int t = T_MIN; t <= T_MAX; ++t) {
    std::cout << std::setw(5) << t;

    for (int i = 6; i >= 0; --i) {
      std::cout << std::setw(12) << std::setprecision(4)
                << std::scientific << table[i][t];
    }

    std::cout << "\n";
  }

  return 0;
}