What Is Turtle Command Problem ?

Turtle is on a N * N grid, with N obstacles. The turtle can only move F orward one position and can turn L eft or R ight. The grid has 4 directions N, E, W, S

Assuming that the initial position of turtle is 1, 1 (bottom left corner of the grid facing North) and the grid has random obstacles in a few of its cells, given the movement instructions, find the final position of turtle and printing the grid state will be an added plus. When there is an obstacle, movement is not possible.

Dividing the problem in to Two parts

1.Code to move turtle as per user instruction
2.Create a grid n*n with n hurdles

Mostly I use ruby but this is my first code with python because we have turtle module in python it will help to solve this problem in easiest way

1.Code to move turtle as per user instruction

Importing Modules

import turtle 
import re 

turtle module to move a object from one place other place as per user instruction
re module helps in regular expression part

Get Instruction from user

print "Enter a Instruction with the following words: F,R,L \n",
instruct = raw_input()

instructFilter = re.sub(r'[^flrFLR]', '', instruct)

print "Accepted string from your Input \n"
print instructFilter
instructArray = list(instructFilter)

In the above snippet We can get the value from user for instruction like “ffFFFFLRRRLlrflrflrflffffff” and this re.sub(r'[^flrFLR]', '', instruct) function remove unwanted letters from the string

f- forward r- turn right l- turn left

Moving the turtle as per instruction

totalLength = len(instructArray)
for index in range(len(instructArray)):
  if instructArray[index] == 'f':
	  turtle.forward(1)
  elif instructArray[index] == 'r':
	  turtle.right(90)
  elif instructArray[index] == 'l':
    turtle.left(95)

  # Last cycle of for loop
  if index == totalLength -1:
		print turtle.pos()

Using for loop iteration process will happen for each instruction in a array-instructArray
Inside conditions

turtle.forward(1) - will move forward the turtle turtle.right(90) - will turn the turtle to right side turtle.left(90) - will turn the turtle to left side and turtle.pos() - will print the current position of turtle

Code Exit from execution

print "Press Enter to exit \n",
process = raw_input()
print process

put the above code into file name it with .py ex index.py and run python index.py you will see the out put like this

Image will come here

2.Create a grid n*n with n hurdles

Modules

import random # module to generate random value  random mobule helps to genrate randome no , we can use this for hurdles

Get N value from user

# Initial setup
board = []
print "Enter N value to build grid and hurdles \n",
grid_value = int(raw_input())

Now the N value is stored in var grid_value

Build N*N Grid with N Hurdles

for row in range(grid_value):
  board.append([])
  random_value = random.randint(0,grid_value-1)
  for column in range(grid_value):
    if column == random_value & column != 0:
      board[row].append('1')
    else:
      board[row].append('0')

using for I can build N*N grid and inserted Hurdles value in random place

Print the Grid

def print_board(board):
  for row in board:
    print " ".join(row)

print_board(board)

Using the above code you can see the generated Grid with random Hurdles 0 - Empty point 1 - Hurdle point

Now the Pending Work is How to connect these two programs.My thought If we connected the program together we can solve the problem and we can get the exact solution for tha problem.

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