13vii.cpp

《C/C＋＋程序设计导论（第二版）》一书的程序源文件

// Maze.cpp  Implementation file for the Maze class

#include <iostream.h>
#include "Maze.h"

void Maze::Solve (int x, int y)
{ 	Recursive_Solve (x, y);
	cout << " maze is solved" << endl;
}

int Maze::Recursive_Solve (int x, int y)
{ int success = 0;
  switch (cells[x][y])
	{	case 'g' :			success = 1; break;
		case '*' :			success = 0; break;
		case 'f' :			success = 0; break;
		default  :			cells[x][y] = 'f';	// leave a footprint..
					success = Recursive_Solve(x+1, y) +
						Recursive_Solve(x-1, y) +
						Recursive_Solve(x, y+1) +
					Recursive_Solve(x, y-1);  break;
	}
	if (success > 0) cout << x << "," << y << endl;
	return (success);
}

void Maze::Input (istream& in)
{  int row, col;
	for (row=0; row<10; row++)
	  for (col=0; col<10; col++)
		in >> cells[col][row];
}

// wrapper function for the extraction operator
istream& operator >> (istream& in, Maze& m)
{	m.Input (in);
	return (in);
}