Microsoft Small Basic

Program Listing:

playerX = 0 'initial player location
playerY = 0
maze[ playerX + ":" + playerY ] = "·" 'set the square of the maze at the player location to be empty so that it will always draw the first time through
GraphicsWindow.FontSize = 24 'increase/decrease this to make the squares bigger/smaller
GraphicsWindow.KeyUp = Move 'move when the player releases the key so that they have to press it once for each movement
Move() 'call move to draw the game for the first time otherwise screen will be blank until they press a key
Sub Move
  newX = playerX 'make a copy of the player's current location
  newY = playerY
  If ( GraphicsWindow.LastKey = "Up" ) Then 'check if the player is moving and if so change the copy of the location accordingly
    newY = newY - 1
  ElseIf ( GraphicsWindow.LastKey = "Down" ) Then
    newY = newY + 1
  ElseIf ( GraphicsWindow.LastKey = "Left" ) Then
    newX = newX - 1
  ElseIf ( GraphicsWindow.LastKey = "Right" ) Then
    newX = newX + 1
  EndIf
  location = newX + ":" + newY 'set location to the new position
  CheckMazeAtLocation() 'the square of maze at this location might not have been created yet
  If ( maze[ location ] <> "■" ) Then 'only update position and draw if they're not trying to move into a wall
    If( maze[ location ] = "☆" ) Then 'if the player walked onto a star...
      score = score + 1  'give them a point
      maze[ location ] = "·" 'remove the star and place an empty floor here instead
    EndIf
    playerX = newX 'update the player location
    playerY = newY
    For y = 0 To 17 'draw a section of the maze that is 18 x 18 tiles in size
      For x = 0 to 17
        location = ( x - 9 + playerX ) + ":" + ( y - 9 + playerY ) 'turn x and y into a location relative to the player
        CheckMazeAtLocation() 'the part of the maze at this location might not have been created yet
        GraphicsWindow.BrushColor = "MidnightBlue" 'clearing each square individually flickers less than a GraphicsWindow.Clear()
        GraphicsWindow.FillRectangle( x * GraphicsWindow.FontSize,  y * GraphicsWindow.FontSize, GraphicsWindow.FontSize, GraphicsWindow.FontSize )
        GraphicsWindow.BrushColor = "PaleGreen" 'draw the maze square at this location
        GraphicsWindow.DrawText( x * GraphicsWindow.FontSize, y * GraphicsWindow.FontSize, maze[ location ] )
      EndFor
    EndFor
    GraphicsWindow.DrawText( 9 * GraphicsWindow.FontSize, 9 * GraphicsWindow.FontSize, "☻" ) 'draw the player
    GraphicsWindow.Title = "Score: " + score 'draw the score in the title bar
  EndIf
EndSub
Sub CheckMazeAtLocation 'check if the maze is empty at this location and if it is then randomly pick a tile to place here
  If ( Array.ContainsIndex( maze, location ) = "False" and Math.GetRandomNumber( 100 ) = 1 ) Then
    maze[ location ] = "☆" 'star - increases your score
  ElseIf ( Array.ContainsIndex( maze, location ) = "False" and Math.GetRandomNumber( 4 ) = 1 ) Then
    maze[ location ] = "■" 'wall - a square you can't move through
  ElseIf( Array.ContainsIndex( maze, location ) = "False" ) Then
    maze[ location ] = "·" 'floor - a square you can move over
  EndIf
EndSub