//lead the user into a maze and back out again, while searching for a tapestry.
#include <ctype.h>    // Provides toupper
#include <iostream.h> // Provides cin, cout

void eat_line( )
{   char next;
    do     cin.get(next);
    while (next != '\n');
}

bool inquire(const char query[ ])
{   char answer;
    do
    {   cout << query << " [Yes or No]" << endl;
        cin >> answer;
        answer = toupper(answer);
        eat_line( );
    }
    while ((answer != 'Y') && (answer != 'N'));
    return (answer == 'Y');
}

bool deadend()
// Postcondition:The return value is true if the direction directly in front
// is a deadend (i.e., a direction that cannot contain the tapestry).
{   return inquire("Are you facing a wall?")  ||
           inquire("Is your name written in front of you?");
}

bool traverse_maze()
{   int direction;   // Counts 1, 2, 3 for the three directions to explore
    bool found;      // Set to true if we find the tapestry

    cout << "Step forward & write your name on the ground." << endl;
    found = inquire("Have you found the tapestry?");

    if (found)
    {   // Pick up the tapestry and step back from whence you came.
	     cout << "Pick up the tapestry and take a step backwards." << endl;
    }
    else
    {   // Explore the three directions (not counting the one that you just
	     // came from). Start with the direction on your left, and then
	     // turn through each of the other possible directions one at a time.
	     cout << "Please turn left 90 degrees." << endl;
	     for (direction = 1; direction <= 3; direction++)
	     {
	         if ( !found && !deadend( ) ) // Not found and Not deadend
		         found = traverse_maze( );
            cout << "Please turn right 90 degrees." << endl;
        }
	     // User is now facing the direction from whence he/she came, so step
	     // forward and turn around. This will put the user in the exact
	     // spot that he/she started was in at the start of this function call.
	     cout << "Please step forward, then turn 180 degrees." << endl;
    }
    return found;
}

void main()
{   if (traverse_maze())
	    cout << "You found it!" << endl;
    else
	    cout << "It wasn't found!" << endl;
}