cCS, C++ code

· To learn to use 2D array (Lab #8)

Robot Motion

A robot has been programmed to follow the instructions in its path. Instructions for the next direction the robot is to move are laid down in a grid. The possible instructions are

· north (up the page)

· south (down the page)

· east (to the right on the page)

· west (to the left on the page)

For example, suppose the robot starts on the north (top) side of Grid 1 and starts south (down). The path the robot follows is shown. The robot goes through 10 instructions in the grid before leaving the grid.

Compare what happens in Grid 2: the robot goes through 3 instructions only once, and then starts a loop through 8 instructions, and never exits.

You are to write a program that determines how long it takes a robot to get out of the grid or how the robot loops around.

There will be one or more grids for robots to navigate. The data for each is in the following form. On the first line are three integers separated by blanks: the number of rows in the grid, the number of columns in the grid, and the number of the column in which the robot enters from the north. The possible entry columns are numbered starting with zero at the left. Then come the rows of the direction instructions. Each grid will have at least one and at most 10 rows and columns of instructions. The lines of instructions contain only the characters N, S, E, or W with no blanks. The end of input is indicated by a row containing 0 0 0.

For each grid in the input there is one path(or showing loop) map. Either the robot follows a certain number of instructions and exits the grid on any one the four sides or else the robot follows the instructions on a certain number of locations once, and then the instructions on some number of locations repeatedly. The sample input below corresponds to the two grids above and illustrates the two forms of output.

Sample input data

3 6 4

NEESWE

WWWESS

SNWWWW

4 5 0

SESWE

EESNW

NWEEN

EWSEN

0 0 0

Sample output

Robot found a path.

000110

110110

011110

Robot is stuck in a loop.

10110

11111

00111

00000

Open Lab Evaluation Form

OLA3 account # C________ Name: ____________________________

Soft copy	Soft copy was not submitted	-90
specification	Solve the assigned problem using methods described in program description.	-90
Execution	Compile without errors.	-80
Execution	Execute without crashing.	-50
documentation	Main Comment Block (file name (1), due date (1), author(1), course #(1) description(4), input/output(2).).	__/-10
documentation	Each variable documented.	__/-5
documentation	Each section of statements in the program well documented.	__/-10
documentation
Style	Use indentation and white space to make the program easier to read.	__/-10
Style	Meaningful names for constants and variables.	__/-5
Output	The program output well formatted. (spacing, indentation etc.)	__/-5
Output	The program output properly labeled and identified.	__/-5
specification	The program output meets the problem specification.	__/-5
specification	Work for all data and produce correct answers -- when there is a path	__/-20
specification	Work for all data and produce correct answers -- when there is a loop	__/-10
correctness	end of input is processed correctly	__/-10
correctness	Work for all data and produce correct answers.  Program will be tested with various data file.	__/-50