COL100 Assignment 6 -Solved

1. Every problem description is followed by some examples showing how exactly input and output is 
being expected. Please refer to them for more clarity. 
2. You must not change the parameters and the names of the functions provided in the skeleton 
code unless clearly specified. 
3. All the inputs/outputs are integers unless explicitly mentioned. 
4. If you still have any more doubts, feel free to shoot them at Piazza. 
5. You can only use lists or arrays to store the data in the questions. 
6. Remember to not to import anything and you can use common inbuilt functions like append/s
plit/len/etc freely. 

1 Lunch Break 
Consider the arrangement of plates in your mess. You have to write a program to let students have 
their lunch properly. The plate which is at the top is the first one to be picked by a student. Whenyou add a plate you always add to the top of the arrangement of the plates. Each plate has a unique 
integer number, call it the plate ID, assigned. Note that this is not related to the position/order or the 
arrangement. As students come to lunch they pick up plates for lunch. 
In this question you will need to implement three operations - AddPlate, PickPlate and Check. 
AddPlate add a new plate with given plate ID on the top of arrangement ,PickPlate removes the top 
most plate from the arrangement and Check returns the top most plate ID in the arrangement. 
You may implement these as functions named AddPlate(), PickPlate() and Check() for the oper
ations AddPlate, PickPlate and Check respectively. You don’t need to worry about the efficiency 
of these operations/functions. We have provided you with a basic skeleton code that you have to fill, 
please download that from Gradescope and fill in the functions. You can implement them however you 
want. The aim of providing it is to make sure you use functions and make them a habit. You can’t 
change the name of the function and parameters of a function. The code has comments which will be 
explaining it well. 
The only time you will be printing Plate ID is when the Check is called and you will also print 
when there is an invalid operation. When you try to Check or PickPlate when no plate is present, 
print Invalid. 
The first line of input is the amount of queries to be processed. Invalid, which is to be printed, 
is case sensitive. 
NOTE: Queries like "AddPlate 5" and "Check" are given as string input and you have to call 
the function with appropriate parameters (if any) from these input strings 
NOTE: Each Queries will be in new line. Please be careful with indentation and case sensitivi
ties 
NOTE: Only print integers. No need to use %.2f 
NOTE: In this question we will be checking ONLY your output so make sure it follows the correct 
format. Your functions returned value will not be checked. But if functions are not used marks will be 
deducted. 
Example 1: 
INPUT: 
1 7 
2 AddPlate 5 
3 Check 
4 AddPlate 4 
5 Check 
6 AddPlate 3 
7 PickPlate 
8 Check 
OUTPUT: 
1 5 
2 4 
3 4 
EXPLANATION: 
• Initially the line is empty. 
2• The first operation is AddPlate 5. So we add a plate with ID 5 into the line. 
• Next operation called is Check so Check prints the plate at the top of the arrangement which is 
5. 
• Then we AddPlate 4 as well thus the arrangement now have plates 5, 4 with 4 at the top. 
• Check prints 4 which is currently at the top of the arrangement. 
• We AddPlate 3 to the line making it 5, 4, 3 with 3 at the top. The line currently is 5, 4, 3. 
• We then PickPlate 3 a ticket as it is on the top of the arrangement -we are left with 5, 4. 
• Check prints 4. 
Example 2: 
INPUT: 
1 8 
2 AddPlate 3 
3 AddPlate 1 
4 Check 
5 PickPlate 
6 Check 
7 PickPlate 
8 Check 
9 PickPlate 
OUTPUT: 
1 1 
2 3 
3 Invalid 
4 Invalid 
EXPLANATION: 
We add Plate 3 and 1 making it {3, 1} then for Check we receive 1. Then We pick the top most plate 
which is 1 and we are left with 3 thus check prints 3. We pick the last plate and now there are no plates 
left so the operations - Check and PickPlate are "Invalid". 
Example 3: 
INPUT: 
1 9 
2 AddPlate 53 
3 AddPlate 67 
4 Check 
5 PickPlate 
6 AddPlate 72 
7 Check 
8 PickPlate 
9 PickPlate 
10 PickPlate 
OUTPUT: 
1 67 
2 72 
3 Invalid 
32 Movie Time (
Consider people in a line to buy a movie ticket. You are the ticket booth operator and want to create a 
program to give tickets to the people in the line. Each person has a unique integer,which is also called 
Aadhar ID (It can be any integer and not necessarily original 12 digit ID) , assigned and is used to iden
tify the person. As people come you keep on issuing tickets to them. The person at the beginning of the 
line is the first one to receive the movie ticket, therefore a person who arrived earlier will get their ticket 
first and then that person leaves the line. One person will only take one ticket. Initially the line is empty. 
In this question you will be doing four operations - Join, Issue, GetLine and Check. Join adds a 
person into the line of people in the end of the line, Issue issues a ticket to the front most person 
and that person leaves the line and Check gives the Aadhar ID of the person at the beginning of the 
line to check for credentials. GetLine will give us the Aadhar ID of all the people in the line starting 
from the first person to the person in the end (in this order) at that instant separated by a single space. 
You have to implement these as functions named Join(), Issue(), GetLine() and Check() for 
the operations Join, Issue, GetLine and Check respectively. You don’t need to worry about the 
efficiency of these operations/functions. We have provided you with a basic skeleton code that you 
have to fill, please download that from Gradescope and fill in the functions. You can implement them 
however you want. The aim of providing it is to make sure you use functions and make them a habit. 
You can’t change the name of the function and parameters of a function. The code has comments 
which will be explaining it well. 
You will be printing the ID when Check and GetLine is called. If there is no person in the line 
and Check, Issue or GetLine is called, print Invalid. 
Input: The first line of input is the number of operations, call it n, that will be given. The next n 
lines will contain the operation. When Join will be called there would be a number followed which will 
be the ID of the person which joins at the end of the line. 
Output: Only print the output asked (no prompts or error code is to be printed). Print the Aadhar 
ID when the operations GetLine and Check are given or Invalid when there is a invalid operation 
called. Only print integers. Invalid, which is to be printed, is case sensitive 
NOTE: Queries like "Join 5" ; "Check" are given as string input and you have to call the func
tion with appropriate parameters (if any) from these input strings 
NOTE: Each Queries will be in new line. Please be careful with indentation and case sensitivi
ties 
NOTE: Only print integers. No need to use %.2f 
NOTE: In this question we will be checking ONLY your output so make sure it follows the correct 
format. Your functions returned value will not be checked. But if functions are not used marks will be 
deducted. 
Example 1: 
INPUT: 
1 10 
2 Join 5 
3 Check 
44 Join 4 
5 Check 
6 GetLine 
7 Join 3 
8 GetLine 
9 Issue 
10 Check 
11 GetLine 
OUTPUT: 
1 5 
2 5 
3 5 4 
4 5 4 3 
5 4 
6 4 3 
EXPLANATION: 
• Initially the line is empty. 
• The first query is Join 5. So we Join person with ID 5 into the line. 
• Next operation called is Check so Check prints the person in the beginning of the line which is 5. 
• Then we Join 4 as well thus the line now have people 5, 4 with 5 at front. 
• Check prints 5. 
• GetLine prints 5 4. 
• We join 3 to the line making it 5, 4, 3 with 5 at front. The line currently is 5 4 3. 
• We then issue 5 a ticket as he is in the beginning of the line - 5 will take the ticket and will leave 
the line, we are left with 4, 3. 
• Check prints 4 as 4 is currently in the beginning of the line. 
• GetLine prints the current line 4 3 
Example 2: 
INPUT: 
1 11 
2 Join 1 
3 Join 3 
4 GetLine 
5 Check 
6 Issue 
7 GetLine 
8 Check 
9 Issue 
10 Getline 
11 Check 
12 Issue 
OUTPUT: 
1 1 3 
2 1 
3 3 
4 3 
5 Invalid 
6 Invalid 
7 Invalid 
5EXPLANATION: 
We Join 1 and 3 into the line making it 1, 3 with 1 at the front. Then Getline prints 1 3. When 
we do a Check, we receive 1. We issue the front most person which is 1 and we are left with 3 thus 
Getline prints 3 and Check prints 3. We issue 3 a ticket and now the line is empty and the operations 
- GetLine, Check and Issue are Invalid. 
Example 3: 
INPUT: 
1 9 
2 Join 53 
3 Join 67 
4 Check 
5 Issue 
6 Join 72 
7 Check 
8 Issue 
9 Issue 
10 Issue 
OUTPUT: 
1 53 
2 67 
3 Invalid 
EXPLANATION: 
Our line has 53, 67 so we check the person with ID 53. We issue 53 with a ticket and are left with 
67. 72 joins the line making our line 67, 72. We check the person with ID 67. We issue 67 and 72 but 
cannot issue anymore tickets and print Invalid. 
3 The weird restaurant - Smart or fool? (15 marks) 
In a town, there is a restaurant which is famous because it has a weird method of operation. It provides 
its customer an ID (which is unique and has nothing to do with the arrival order of the customers) and 
the bill amount to be paid. The restaurant thinks that by giving privilege to the customer with higher 
bill amount they can provoke the customers to pay more so that they get their order faster. Hence the 
restaurant will serve the customer first which has the highest bill amount in the waiting line. If the bill 
amount is same then the customer which came first will be served first. 
In this question, you will be implementing three operations - Order, Serve and Highest. Order 
inserts the customer into the waiting line, Serve serves the highest bill customer and thus the customer 
will leave the waiting line which has the highest bill amount, Highest gives the customer ID number 
having the highest bill amount in the waiting line at the moment. Note that if the bill amount is same, 
the customer ID that was inserted first in the chronological order is considered. 
Input: First line contains an integer which indicates the number of operations to be performed. 
From next line on wards the operations are followed. When calling Order, we provide two space 
separated numbers, first number is the customer ID to be inserted, and the second number is the bill 
amount for the customer. Refer to the examples below for more clarity. 
Output: You will be printing the customer ID only when Highest is called. If you call High
est or Serve, when no element is present, print Invalid. Also note that There may be multiple orders 
with same bill amount inserted. 
6You may implement these as functions named Order(), Serve() and Highest() for the opera
tions Order, Serve and Highest respectively. You don’t need to worry about the efficiency of these 
operations/functions. We have provided you with a basic skeleton code that you have to fill, please 
download that from Gradescope and fill in the functions. You can implement them however you want. 
The aim of providing it is to make sure you use functions and make them a habit. You can’t change the 
name of the function and parameters of a function. The code has comments which will be explaining it 
well. 
NOTE: Queries like "Order 5 20" ; "Highest" are given as string input and you have to call the 
function with appropriate parameters (if any) from these input strings 
NOTE: Each Queries will be in new line. Please be careful with indentation and case sensitivi
ties 
NOTE: Only print integers. No need to use %.2f 
NOTE: In this question we will be checking ONLY your output so make sure it follows the correct 
format. Your functions returned value will not be checked. But if functions are not used marks will be 
deducted. 
Example 1: 
INPUT: 
1 8 
2 Order 5 20 
3 Highest 
4 Order 4 100 
5 Highest 
6 Order 3 100 
7 Highest 
8 Serve 
9 Highest 
OUTPUT: 
1 5 
2 4 
3 4 
4 3 
EXPLANATION: 
When we insert 5 into the waiting line having bill amount as 20. Calling Highest would print 5. We 
insert 4 having bill amount as 100. Calling highest now would print 4 as customer with ID 4 has highest 
bill amount till now. We then insert 3 having bill amount as 100. Calling Highest would still print 4 
because even though 4 and 3 have the same bill amount, 4 would be considered since it was inserted 
before 3. Remove now removes 4 from the waiting line. Highest now prints 3 as the customer with ID 3 
has higher bill amount than customer with ID 5. 
Example 2: 
INPUT: 
1 8 
2 Order 1 22 
3 Order 7 23 
4 Highest 
75 Serve 
6 Highest 
7 Serve 
8 Highest 
9 Serve 
OUTPUT: 
1 7 
2 1 
3 Invalid 
4 Invalid 
EXPLANATION: 
When we insert 1 into the waiting line with bill 22, then we insert 7 into waiting line with bill 23. We 
get the highest order which is 7 with bill amount 23. Then we serve the highest order leaving only 
order 1 in the waiting line. Highest gives us order 1 as it’s the only one left. We serve the order 1 and 
are left with an empty waiting line. The operations Highest and Serve are Invalid. 
Example 3: 
INPUT: 
1 6 
2 Order 53 1 
3 Order 67 2 
4 Highest 
5 Serve 
6 Order 72 3 
7 Highest 
OUTPUT: 
1 67 
2 72 
EXPLANATION: 
Orders 53 and 67 are placed with bill amounts 1 and 2 respectively. The highest is order 67 with bill 
amount 2, which is then served. The order 72 is placed with bill amount 3. There are two orders in 
waiting 72 and 53 with bill values 3 and 1 and the highest is 72. 
Note: No operation other than Order, Highest and Serve is called. Make sure of case sensitive 
output when printing Invalid 
4 Matrix Operations(20 Marks) 
Python doesn’t have a built-in type for matrices. However, in this assignment, we will treat a 
list of a list of floats as a matrix. Each sub-list inside the outer list is a row in the matrix. In this 
question you need to implement some matrix operations. We have provided you with a skeleton code 
that you have to fill, please download that from Gradescope and fill in the functions.You can implement 
them however you want. The aim of providing it is to make sure you use functions and make them a 
habit. You have to implement the functions in the exact manner as given in the skeleton code, i.e., you 
can’t change the parameters of a function and their return types. In this question you don’t need 
to take any input or print any output, we will be calling your functions, you just have to 
return the values. 
8IMPORTANT NOTE: In this question we will not be giving any input nor expecting any output. 
Only the values returned from the functions will be checked so make sure the functions work properly. 
An example matrix :- [[1.00,2.00,3.00],[4.00,5.00,6.00],[7.00,8.00,9.00]], the matrix 
represented by the given list of lists is :- 
NOTE: YOU DO NOT WORRY ABOUT FORMATTING OF THE CONTENTS OF 
THE MATRIX. PERFORM THE OPERATION ON THE MATRIX AS IT IS GIVEN TO 
THE FUNCTION AND RETURN THE COMPUTED OUTPUT MATRIX WITHOUT 
ANY FORMATTING FOR DECIMAL PLACES. 
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7.00 8.00 9.00 
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4.1 Check Matrix
This is a function that checks whether the list of list is a matrix or not. A valid matrix has the property 
that each row has the same number of columns AND all the elements of the matrix are float values 
AND every valid matrix has at least one element inside it. Your function will return a Boolean value - 
True if the list of lists is a matrix and False if it is not. The function name is CheckMatrix(). Some 
samples test cases are - 
Example 1: 
Argument: 
1 [[1.00]] 
Return: 
1 True 
Example 2: 
Argument: 
1 [[]] 
Return: 
1 False 
Example 3: 
Argument: 
1 [[1.00,1.00],[2.00]] 
Return: 
1 False 
Example 4: 
Argument: 
1 [[1.00,2.00],[2.00,3.00]] 
Return: 
1 True 
Example 5: 
Argument: 
1 [["Hello",5.00],[]] 
Return: 
91 False 
Example 6: 
Argument: 
1 [] 
Return: 
1 False 
Note: This function has to be used in every function after this. 
4.2 Transpose 
The function Transpose() does transpose of a matrix, it takes a matrix as input and returns its 
transpose. You also have to check if the list given is a matrix first and None must be returned if the 
list is not a matrix. The list of list returned must have the correct dimensions i.e. if the transpose has 
dimensions - 5×3 there must be 5 sub lists (or rows) with 3 elements each. Some samples test cases are - 
Example 1: 
Argument: 
1 [[1.00]] 
Return: 
1 [[1.00]] 
Example 2: 
Argument: 
1 [[1.00,2.00],[3.00,4.00]] 
Return: 
1 [[1.00,3.00],[2.00,4.00]] 
Example 3: 
Argument: 
1 [[1.00,1.00],[2.00]] 
Return: 
1 None 
Example 4: 
Argument: 
1 [[1.00,2.00,3.00],[4.00,3.00,9.00]] 
Return: 
1 [[1.00,4.00],[2.00,3.00],[3.00,9.00]] 
Example 5: 
Argument: 
1 [["Hello",5.00],[]] 
Return: 
1 None 
Example 6: 
Argument: 
1 [[1.00,4.00]] 
Return: 
1 [[1.00],[4.00]] 
104.3 Addition 
The function Addition() takes two lists of lists (matrices) and returns the addition of them (if it 
exists). If any of the lists of lists is not a matrix or if the operation cannot be done,i.e. the dimnsion 
of the two matrices are not same, None has to be returned. Matrix addition is defined between two 
matrices if they have the same dimensions. 
Matrix addition between two matrices [aij ]m×n and [bij ]m×n is defined as [aij + bij ]m×n 
Some samples test cases are - 
Example 1: 
Argument: 
1 A = [[1.00]], B = [[2.00]] 
Return: 
1 [[3.00]] 
Example 2: 
Argument: 
1 A = [[1.00,2.00],[3.00,4.00]], B = [[7.00,8.00],[4.00,1.00]] 
Return: 
1 [[8.00,10.00],[7.00,5.00]] 
Example 3: 
Argument: 
1 A = [[1.00,1.00]], B = [[2.00]] 
Return: 
1 None 
Example 4: 
Argument: 
1 A = [[1.00,2.00,3.00],[4.00,3.00,9.00]], B = [[1.00,4.00],[2.00,3.00],[3.00,9.00]] 
Return: 
1 None 
Example 5: 
Argument: 
1 A = [["Hello",5.00],[]] , B = [[1.00]] 
Return: 
1 None 
Example 6: 
Argument: 
1 A = [[1.00,4.00]], B = [[0.00,4.00]] 
Return: 
1 [[1.00,8.00]] 
114.4 Multiplication 
The function Multiplication() takes two lists of lists (matrices) and returns the multiplication 
of them (if it exists). If the operation cannot be done None has to be returned. Matrix multi
plication is defined between two matrices if the dimension of first matrix’s column is equal to the 
dimension of second matrix’s row. The multiplication can be done via any algorithm you like. Mul
tiplication won’t be performed when either of the list of list is not a matrix. Some samples test cases are - 
Example 1: 
Argument: 
1 A = [[1.00]], B = [[2.00]] 
Return: 
1 [[2.00]] 
Example 2: 
Argument: 
1 A = [[1.00,2.00],[3.00,4.00]], B = [[7.00,8.00],[4.00,1.00]] 
Return: 
1 [[15.00,10.00],[37.00,28.00]] 
Example 3: 
Argument: 
1 A = [[1.00,1.00]], B = [[2.00]] 
Return: 
1 None 
Example 4: 
Argument: 
1 A = [[1.00,2.00,3.00],[4.00,3.00,9.00]], B = [[1.00,4.00],[2.00,3.00],[3.00,9.00]] 
Return: 
1 [[14.00,37.00],[37.00,106.00]] 
Example 5: 
Argument: 
1 A = [["Hello",5.00]], B = [[]] 
Return: 
1 None 
Example 6: 
Argument: 
1 A = [[1.00,4.00]], B = [[0.00,4.00]] 
Return: 
1 None 
124.5 Symmetric 
This function Symmetric() takes in a list of lists (or matrix) and returns a Boolean value True if the 
matrix is symmetric and False if it is not a symmetric matrix. If the list of list given is not a matrix 
or not a square matrix please return False. A symmetric matrix is defined as the square matrix that 
is equal to its transpose matrix. Symmetric Matrices are only defined for square matrices and return 
False for the rest. Some samples test cases are - 
Example 1: 
Argument: 
1 [[1.00]] 
Return: 
1 True 
Example 2: 
Argument: 
1 [[1.00,2.00],[2.00,1.00]] 
Return: 
1 True 
Example 3: 
Argument: 
1 [[1.00,1.00],[1.00]] 
Return: 
1 False 
Example 4: 
Argument: 
1 [[1.00,1.00],[1.00,1.00]] 
Return: 
1 True 
Example 5: 
Argument: 
1 [[1.00,2.00,3.00],[2.00,1.00,7.00]] 
Return: 
1 False 
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