Copy the program debug_stringcmp.c from the course account to your directory by typing (make sure you type the dot at the end):

cp ~dp1091/public_html/24T3/activities/debug_stringcmp/debug_stringcmp.c .

Debugging Tips!

Some debugging tips for you:

• dcc output - as you run into issues, dcc will point you to where the errors are. Remember that dcc gives you the line number the issue is on, and will give some sort of explanation. Make sure you read everything dcc gives you. Sometimes we get “errors carried forward”, so find your first error, fix that, then recompile.
• print statements - sometimes it can be handy to see if the flow of your code puts you in the spot you expect it to be (ie. inside the right if statement, or going through a loop the correct amount of times). A quick way you can check this is by putting print statements in your code for testing purposes, like "the value of x is %d and y is %d". This lets you check that you got against what you expected.
• DPST1091 debugging guide

The Task

This exercise takes in two strings as input, calcuates if they are equal and prints out the result. Currently it has some issues - it is your job to figure them out and fix the code.

Examples

dcc debug_stringcmp.c -o debug_stringcmp
./debug_stringcmp
Enter the first string: Hello, World!
Enter the second string: Hello, World!
The strings are equal!
./debug_stringcmp
Enter the first string: It's illegal to own just one guinea pig in Switzerland
Enter the second string: Pigeons can tell the difference between Picasso and Monet
The strings are not equal!

1091 style debug_stringcmp.c
    

When you think your program is working, you can use autotest to run some simple automated tests:

1091 autotest debug_stringcmp

When you are finished working on this exercise, you must submit your work by running give:

give dp1091 lab06_debug_stringcmp debug_stringcmp.c
    

You must run give before Monday 14 October 09:00 to obtain the marks for this lab exercise. Note that this is an individual exercise, the work you submit with give must be entirely your own.

Write a program called word_square.c that prompts the user to enter a word, and afterwards, prints that word out n amount of times, where n is the length of the word.

You should use the function fgets to scan in the input word.

Examples

dcc word_square.c -o word_square
./word_square
Input word: a

Word square is:
a
./word_square
Input word: word

Word square is:
word
word
word
word
./word_square
Input word: abrakadabra

Word square is:
abrakadabra
abrakadabra
abrakadabra
abrakadabra
abrakadabra
abrakadabra
abrakadabra
abrakadabra
abrakadabra
abrakadabra
abrakadabra

Assumptions/Restrictions/Clarifications

• You can assume that you will be given a word no longer than 1024 character (Including the null-terminator).

1091 style word_square.c
    

When you think your program is working, you can use autotest to run some simple automated tests:

1091 autotest word_square

When you are finished working on this exercise, you must submit your work by running give:

give dp1091 lab06_word_square word_square.c
    

You must run give before Monday 14 October 09:00 to obtain the marks for this lab exercise. Note that this is an individual exercise, the work you submit with give must be entirely your own.

Copy the program alternating_case.c from the course account to your directory by typing (make sure you type the dot at the end):

cp ~dp1091/public_html/24T3/activities/alternating_case/alternating_case.c .

Complete the C program, alternating_case.c.

The main function has already been written for you. You must not modify it in any way.

This function takes in a string, and should modify it so that the first letter is lowercase, and the case of each following letter alternates.

In other words, the string should be modified so that:

• The first letter is lowercase,
• The second letter is uppercase,
• The third letter is lowercase,
• The forth letter is uppercase,
• etc.

All non letter characters should be left unmodified.

Examples

./alternating_case
hello
hElLo
./alternating_case
Hello World
hElLo WoRlD
./alternating_case
The quick brown fox jumps over the lazy dog
tHe QuIcK bRoWn FoX jUmPs OvEr ThE lAzY dOg
./alternating_case
a1b2c3e4d5 f6g7
a1B2c3E4d5 F6g7

Assumptions/Restrictions/Clarifications

• You can assume the string will contain at most 1024 characters

1091 style alternating_case.c
    

When you think your program is working, you can use autotest to run some simple automated tests:

1091 autotest alternating_case

When you are finished working on this exercise, you must submit your work by running give:

give dp1091 lab06_alternating_case alternating_case.c
    

You must run give before Monday 14 October 09:00 to obtain the marks for this lab exercise. Note that this is an individual exercise, the work you submit with give must be entirely your own.

Download simple_snake.c here, or copy it to your CSE account using the following command:

cp -n /import/reed/A/dp1091/public_html/24T3/activities/simple_snake/simple_snake.c .

Snake is one of the oldest and most famous digital games

The Snake game involves controlling a snake that moves along a 2D plane. The goal is to lead this snake to an apple on the map, that upon eating, increases the length of the snake.

As more apples are eaten, the player must be careful as they move the snake, as the game will end if the snake moves back into their tail.

For this exercise, you will be implementing a simpler version of Snake. This version involves:

1. Spawning the snake and the apple
2. Moving the snake up/down/left/right in a loop (using u/d/l/r commands)
3. Ending the game when the snake reaches the apple

Since this game is fundamentally about moving a snake on a 2D plane, it should make sense to represent this as a 2D array in code. In the starter code provided, you should notice that the first line of code in the main() function defines this array as:

enum land map[SIZE][SIZE];

This means that the map is made up only of values defined in the enum land definition above the main() function.

Let's have a look at what each value in enum land represents:

• NOT_VISITED - Indicates a land tile that the snake has not visited yet
• VISITED - Indicates a land tile that the snake has visited
• SNAKE - The land tile the snake is currently on
• APPLE - The land tile the apple is currently on

You have been provided a print_map() function that will print the 2D array with the enum land tiles set.

Make sure you understand everything mentioned above before reading the example below!

Examples

dcc simple_snake.c -o simple_snake
./simple_snake
Welcome to Snake!
Please enter apple location: 2 3
Please enter snake location: 4 3
. . . . . . . . 
. . . . . . . . 
. . . A . . . . 
. . . . . . . . 
. . . S . . . . 
. . . . . . . . 
. . . . . . . . 
. . . . . . . . 
r
. . . . . . . . 
. . . . . . . . 
. . . A . . . . 
. . . . . . . . 
. . . - S . . . 
. . . . . . . . 
. . . . . . . . 
. . . . . . . . 
u
. . . . . . . . 
. . . . . . . . 
. . . A . . . . 
. . . . S . . . 
. . . - - . . . 
. . . . . . . . 
. . . . . . . . 
. . . . . . . . 
u
. . . . . . . . 
. . . . . . . . 
. . . A S . . . 
. . . . - . . . 
. . . - - . . . 
. . . . . . . . 
. . . . . . . . 
. . . . . . . . 
u
. . . . . . . . 
. . . . S . . . 
. . . A - . . . 
. . . . - . . . 
. . . - - . . . 
. . . . . . . . 
. . . . . . . . 
. . . . . . . . 
l
. . . . . . . . 
. . . S - . . . 
. . . A - . . . 
. . . . - . . . 
. . . - - . . . 
. . . . . . . . 
. . . . . . . . 
. . . . . . . . 
d
. . . . . . . . 
. . . - - . . . 
. . . S - . . . 
. . . . - . . . 
. . . - - . . . 
. . . . . . . . 
. . . . . . . . 
. . . . . . . . 
Chomp!

Assumptions/Restrictions/Clarifications

• You will always be given snake/apple locations inside the map
• You will always be given correct direction commands (u/d/l/r)
• You will never be given commands such that the snake walks off the map

1091 style simple_snake.c
    

When you think your program is working, you can use autotest to run some simple automated tests:

1091 autotest simple_snake

When you are finished working on this exercise, you must submit your work by running give:

give dp1091 lab06_simple_snake simple_snake.c
    

You must run give before Monday 14 October 09:00 to obtain the marks for this lab exercise. Note that this is an individual exercise, the work you submit with give must be entirely your own.

Copy the program planter.c from the course account to your directory by typing (make sure you type the dot at the end):

cp ~dp1091/public_html/24T3/activities/planter/planter.c .
Complete the program planter.c!
The program is a garden simulator that uses a 2D array, a 5x5 grid, to represent a garden.
The gardener will be represented by the # character and each round will appear on the first column of the row that is about to be planted.
The program should prompt the user to choose which type of flower that will be planted in each row of the garden. The user may also choose to plant nothing, represented by the . character.
Flowers take 3 rounds to bloom after they are planted. During the round, if the flower is still growing, 
it will be represented by a number that represents how many rounds are left for the flower to bloom. If the flower has already bloomed, 
it will be represented by the first letter of its name.
The garden should be printed after each round, updating how long is left for the flowers to bloom. 
Once all flowers are planted, the program should wait for the growing flowers to bloom, printing Waiting for flowers to bloom... and the garden after each round.
You must use the provided struct garden to represent the flowers in the garden, the print_garden function to display the current state of the garden and the provided enum flowers to represent the different flowers.
Examples
dcc planter.c -o planter
./planter
Welcome to the planter!

# . . . . 
. . . . . 
. . . . . 
. . . . . 
. . . . . 

0. Nothing
1. Daisy
2. Rose
3. Tulip
Which Flower would you like to plant in this row? 3

3 3 3 3 3 
# . . . . 
. . . . . 
. . . . . 
. . . . . 

0. Nothing
1. Daisy
2. Rose
3. Tulip
Which Flower would you like to plant in this row? 0

2 2 2 2 2 
. . . . . 
# . . . . 
. . . . . 
. . . . . 

0. Nothing
1. Daisy
2. Rose
3. Tulip
Which Flower would you like to plant in this row? 1

1 1 1 1 1 
. . . . . 
3 3 3 3 3 
# . . . . 
. . . . . 

0. Nothing
1. Daisy
2. Rose
3. Tulip
Which Flower would you like to plant in this row? 2

T T T T T 
. . . . . 
2 2 2 2 2 
3 3 3 3 3 
# . . . . 

0. Nothing
1. Daisy
2. Rose
3. Tulip
Which Flower would you like to plant in this row? 0

T T T T T 
. . . . . 
1 1 1 1 1 
2 2 2 2 2 
. . . . . 

Waiting for flowers to bloom...

T T T T T 
. . . . . 
D D D D D 
1 1 1 1 1 
. . . . . 

Waiting for flowers to bloom...

T T T T T 
. . . . . 
D D D D D 
R R R R R 
. . . . . 





Assumptions/Restrictions/Clarifications

• Assume you will only be given valid inputs.
• The provided struct garden, enum flowers and print_garden should not be modified.
• You may not assume a flower will always be chosen to be planted in a row, the user may choose to plant nothing.

1091 style planter.c
    

When you think your program is working, you can use autotest to run some simple automated tests:

1091 autotest planter

When you are finished working on this exercise, you must submit your work by running give:

give dp1091 lab06_planter planter.c
    

You must run give before Monday 14 October 09:00 to obtain the marks for this lab exercise. Note that this is an individual exercise, the work you submit with give must be entirely your own.

A palindrome is a sequence which is the same forwards as backwards.

Write a program, palindrome.c, which reads a string and tests if it is a palindrome.

For example:

./palindrome
Enter a string: kayak
String is a palindrome
./palindrome
Enter a string: canoe
String is not a palindrome
./palindrome
Enter a string: if if fi fi
String is a palindrome
./palindrome
Enter a string: if if if fi
String is not a palindrome

Hint: don't use scanf, use fgets to read the string.

Note, your program needs to read only one line - it doesn't have to read until the end of input.

You can assume the line contains at most 4096 characters.

1091 style palindrome.c
    

When you think your program is working, you can use autotest to run some simple automated tests:

1091 autotest palindrome

When you are finished working on this exercise, you must submit your work by running give:

give dp1091 lab06_palindrome palindrome.c
    

You must run give before Monday 14 October 09:00 to obtain the marks for this lab exercise. Note that this is an individual exercise, the work you submit with give must be entirely your own.

Write a C function that removes duplicate elements from an array, by copying the non-duplicate values to a second array, i.e. only the first occurrence of any value should be copied.

Place your answer in a file named remove_duplicates_function.c

Your function should take three parameters: the length of source array, the source array itself, and the destination array. It must have this prototype:

int remove_duplicates(int length, int source[length], int destination[length]);

Your function should return a single integer: the number of elements copied to the destination array.

For example, if the source array contains these 6 elements:

3, 1, 4, 1, 5, 9

Your function should copy these 5 values to the destination array:

3, 1, 4, 5, 9

Your function should return the integer 5, because there were 5 values copied -- the second occurrence of the digit 1 was not copied.

Assumptions/Restrictions/Clarifications

• You can assume the source array only contains positive integers.
• You can assume the source array contains at least one integer.
• You can assume that the destination array will always be large enough to fit all of the copied values.
• You cannot assume anything about the number of duplicates, i.e. there may not be any duplicates, or conversely, the entire array may be duplicates.
• Your function should return a single integer.
• Your function should not change the array it is given.
• Your function should not call scanf (or getchar or fgets).
• Your function should not print anything. It should not call printf.
• Your submitted file may contain a main function. It will not be tested or marked.

Write a C function that removes duplicate elements from an array, by copying the non-duplicate values to a second array, i.e. only the first occurrence of any value should be copied.

Place your answer in a file named remove_duplicates_function.c

Your function should take three parameters: the length of source array, the source array itself, and the destination array. It must have this prototype:

int remove_duplicates(int length, int source[length], int destination[length]);

Your function should return a single integer: the number of elements copied to the destination array.

For example, if the source array contains these 6 elements:

3, 1, 4, 1, 5, 9

Your function should copy these 5 values to the destination array:

3, 1, 4, 5, 9

Your function should return the integer 5, because there were 5 values copied -- the second occurrence of the digit 1 was not copied.

Assumptions/Restrictions/Clarifications

• You can assume the source array only contains positive integers.
• You can assume the source array contains at least one integer.
• You can assume that the destination array will always be large enough to fit all of the copied values.
• You cannot assume anything about the number of duplicates, i.e. there may not be any duplicates, or conversely, the entire array may be duplicates.
• Your function should return a single integer.
• Your function should not change the array it is given.
• Your function should not call scanf (or getchar or fgets).
• Your function should not print anything. It should not call printf.
• Your submitted file may contain a main function. It will not be tested or marked.

1091 style remove_duplicates_function.c
    

When you think your program is working, you can use autotest to run some simple automated tests:

1091 autotest remove_duplicates_function

When you are finished working on this exercise, you must submit your work by running give:

give dp1091 lab06_remove_duplicates_function remove_duplicates_function.c
    

You must run give before Monday 14 October 09:00 to obtain the marks for this lab exercise. Note that this is an individual exercise, the work you submit with give must be entirely your own.

Download largest_z_sum.c here, or copy it to your CSE account using the following command:

cp -n /import/reed/A/dp1091/public_html/24T3/activities/largest_z_sum/largest_z_sum.c .

You are to implement the largest_z_sum function which should return the sum of values forming the shape of the letter 'Z' in a square 2D array.

A Z shape is made up of three lines of equal length. Two of these lines are horizontal and one is diagonal. The length of the three lines must be equal but can range from 3 up to the size of the array. Only correctly oriented Z shapes are valid - Z shapes with a northwest/southeast diagonal are not valid.

The 2D square array may contain any positive or negative integers.

You can assume that the side length of the 2D square array will always be greater than or equal to 3.

You can assume that the side length of the 2D array will never be greater than

1. The file largest_z_sum.c contains a main function which reads values into a square 2D array and calls largest_z_sum.

Examples

dcc largest_z_sum.c -o largest_z_sum
./largest_z_sum
Enter 2D array side length: 3
Enter 2D array values:
1 1 1
1 1 1
1 1 1
The largest z sum is 7.
./largest_z_sum
Enter 2D array side length: 5
Enter 2D array values:
1  2  3  4  5
6  7  8  9  10
11 12 13 14 15
16 17 18 19 20
21 22 23 24 25
The largest z sum is 169.
./largest_z_sum
Enter 2D array side length: 5
Enter 2D array values:
 28 -47 -40  29  49
 26 -42 -37  48  1
-36  50  41 -24 -33
 41  25 -39  39  48
 14 -26 -46 -3  -29
The largest z sum is 153.
./largest_z_sum
Enter 2D array side length: 5
Enter 2D array values:
1  1  1  1  1
1  1  1  1  1
99 99 99 1  1
1  99 1  1  1
99 99 99 1  1
The largest z sum is 693.

In the first example, there is only one possible Z sum of size 3.

The Z in the example input is underlined below for your reference:

1 1 1
1 1 1
1 1 1

In the second example, the Z of size 5 starting from (0, 0) is used to form the largest sum of:

1 + 2 + 3 + 4 + 5 + 9 + 13 + 17 + 21 + 22 + 23 + 24 + 25 = 169

The Z in the example input is underlined below for your reference:

1  2  3  4  5
6  7  8  9  10
11 12 13 14 15
16 17 18 19 20
21 22 23 24 25

In the third example, the Z of size 4 starting from (0, 1) is used to form the largest sum of:

-47 - 40 + 29 + 49 + 48 + 41 + 25 - 39 + 39 + 48 = 153

The Z in the example input is underlined below for your reference:

 28 -47 -40  29  49
 26 -42 -37  48  1
-36  50  41 -24 -33
 41  25 -39  39  48
 14 -26 -46 -3  -29

In the fourth example, the Z of size 3 starting from (2, 0) is used to form the largest sum of:
99 + 99 + 99 + 99 + 99 + 99 + 99 = 693
The Z in the example input is underlined below for your reference:

1  1  1  1  1
1  1  1  1  1
99 99 99 1  1
1  99 1  1  1
99 99 99 1  1

1091 style largest_z_sum.c
    

When you think your program is working, you can use autotest to run some simple automated tests:

1091 autotest largest_z_sum

When you are finished working on this exercise, you must submit your work by running give:

give dp1091 lab06_largest_z_sum largest_z_sum.c
    

You must run give before Monday 14 October 09:00 to obtain the marks for this lab exercise. Note that this is an individual exercise, the work you submit with give must be entirely your own.