Решение 8 Queens в Python

0 Matt [2018-12-11 02:26:00]

Я давно нашел следующий код C в сети и попытался реализовать это решение на Python. Когда я компилирую код C, я получаю ожидаемые результаты; когда я запускаю свой скрипт на Python, я не получаю никакого вывода. Ниже приведен код C и мое преобразование его в Python. Я должен отметить, что я делаю этот небольшой проект, чтобы изучить синтаксис Python. Из того, что я могу сказать в своих слабых попытках отладки, проблема заключается в моей реализации функции diagonalsOK(). Любой совет будет принята с благодарностью!

#include <stdio.h>

/* SOLUTION TO EIGHT QUEENS PROBLEM
Author: Eilon Lipton
Date: 1/26/2000
http://www.yoe.org/progchan/start.shtml

All code is copyright (C) Eilon Lipton, 2000
You may use it for educational purposes but please give me credit
if you show the solution to others.
*/

/* Since this program outputs many lines, you should probably redirect its
output to a file like so:
eightq > solution.txt
and then open the file solution.txt in any text editor to see the
results */

/* This function resets the board to an empty board */
void clearboard(int board[8][8])
{
   int i, j;

for (i = 0; i < 8; i++)
  for (j = 0; j < 8; j++)
     board[i][j] = 0;
}


/* This function prints out the board to the screen using a simple diagram 
*/
void printsolution(int board[8][8])
{
   int i, j;

   for (i = 0; i < 8; i++)
   {
      for (j = 0; j < 8; j++)
      {
         if (board[i][j] == 0)
         {
            printf("*");
         }
         else
         {
            printf("Q");
         }
      }

      printf("\n");
   }

   printf("\n");
}


/* Counts how many queens are in a certain row */
int rowOK(int row, int board[8][8])
{
   int i, counter;

   counter = 0;

   for (i = 0; i < 8; i++)
   {
      counter = counter + board[row][i];
   }

       return counter;
    }


/* Counts how many queens are in the two diagonals crossing a certain place 
*/
int diagonalsOK(int row, int column, int board[8][8]){
int i, counter;

counter = 0;

/* This function is a bit tricky:
  We try every diagonal extending no more than 8 spaces in each of the four 
directions
  (down/left, down/right, up/left, and up/right */
for (i = 1; i < 8; i++) {
  if ((row - i) >= 0) {
     if ((column - i) >= 0) {
        counter = counter + board[row - i][column - i];
     }

     if ((column + i) < 8) 
     {
        /* down/right */
        counter = counter + board[row - i][column + i];
     }
  }

  if ((row + i) < 8)   /* check that row is not out of bounds */
  {
     if ((column - i) >= 0)  /* check that column is not out of bounds */
     {
        /* up/left */
        counter = counter + board[row + i][column - i];
     }

     if ((column + i) < 8)  /* check that column is not out of bounds */
     {
        /* up/right*/
        counter = counter + board[row + i][column + i];
     }
  }
}

return counter;
  }


/* This is the most important function, it is described on the web page */
void addqueen(int column, int board[8][8])
{
   int row;

   for (row = 0; row < 8; row++)
   {
      board[row][column] = 1;

      if ((rowOK(row, board) == 1) &&
      (diagonalsOK(row, column, board) == 0))
      {
         if (column == 7)
         {
            printsolution(board);
         }
         else
         {
            addqueen(column + 1, board);
         }
      }

      board[row][column] = 0;
   }
}


/* Main function */
int main()
{
   int board[8][8];

   printf("Meow?\n");
   clearboard(board);
   addqueen(0, board);

   return 0;
}

Попытка преобразования Python:

board = [[0, 0, 0, 0, 0, 0, 0, 0],
        [0, 1, 0, 0, 0, 0, 0, 0],
        [0, 0, 0, 0, 0, 0, 0, 0],
        [1, 0, 0, 0, 0, 0, 0, 0],
        [0, 0, 0, 0, 0, 0, 0, 0],
        [0, 0, 0, 0, 0, 0, 0, 0],
        [0, 0, 0, 0, 0, 0, 0, 0],
        [0, 0, 0, 0, 0, 0, 0, 0]]

def clearBoard(board):
    for i in range(8):
        for j in range(8):
            board[i][j] = 0

def printBoard(board):
    for i in range(8):
       for j in range(8):
           if board[i][j] == 1:
               print("Q", end="")
           else:
               print("X", end="")
       print("")
    print("")

def rowOK(row, board):
    counter = 0

    for i in range(8):
        counter += board[row][i]
    return counter

def diagsOK(row, col, board):

    counter = 0

    for i in range(8):
        if (row - i) >= 0:
            if (col - i) >= 0:
                counter = counter + board[row - i][col - i]
            if (col + i) < 7:
                counter = counter + board[row - i][col + i]
        if (row + i) < 8:
            if (col - i) >= 0:
                counter = counter + board[row + i][col - i]
            if (col + i) < 8:
                counter = counter + board[row + i][col + i]
    return counter

def addQueen(col, board):
    for row in range(8):
        board[row][col] = 1
        if rowOK(row, board) == 1 & diagsOK(row, col, board) == 0:
        #print("Adding first queen...")
            if col == 7:
                printBoard(board)
            else:
                addQueen(col + 1, board)
        board[row][col] = 0


clearBoard(board)
addQueen(0, board)

c python arrays python-3.x recursion