Page 405 - Computer Science V2.0 Class 11

3. Given a list (say, list1) of numbers, its cumulative list is another list (say, list2) whose ith element is the sum of all
elements till the ith element of lst1. If a list is empty then its cumulative list will also be an empty list. Write a
program that accepts a list of integers and displays its cumulative list.
01 def cumulativeList(lst1):
02 '''
03 Objective: To return another list whose ith element is the sum of all elements
04 till ith element of lst1
05 Input Parameter: lst1- list
06 Return value: cumLst - list
07 '''
08 if len(lst1) == 0 :
09 return []
10 else:
11 cumLst = [lst1[0]] # lst1[0] is sum of 1-element list
12 for i in range(1,len(lst1)):
13 nextElement = cumLst[i-1] + lst1[i]
14 cumLst.append(nextElement)
15 return cumLst
16 # Objective: To find the cumulative sum of elements of an integer list
17 myList = eval(input('Enter a list of numbers: '))
18 result = cumulativeList(myList)
19 print('List of cumulative sums: ' ,result)
Sample Output:

>>> Enter a list of numbers: [1,2,5,2,5]
List of cumulative sums: [1, 3, 8, 10, 15]

4. Develop linearSearch(myTuple, key) that searches a tuple linearly for the required key. It should
take a tuple myTuple and a value key to be searched in myTuple as arguments. When the key is present in
myTuple, the function linearSearch should return True and the index where the search key is found. If

linearSearch reaches the end of the list without finding the key, linearSearch should return False
with None as the index.

01 def linearSearch(myTuple, key):
02 '''
03 Objective: To search the key in myTuple
04 Input Parameters:
05 myTuple: tuple
06 key: element to be searched
07 Return Value:
08 True: if key is found in the tuple, False otherwise
09 index:
10 if search succeeds, index of search key found
11 None, if search fails
12 '''
13 found = False
14 for index in range(len(myTuple)):
15 if myTuple[index] == key:
16 found = True
17 return found, index
18 return found, None
19
20 #main program segment
21 '''
22 Objective: To search for a key in a tuple
23 User Interface:
24 1. User is prompted to enter a tuple.

Lists and Tuples 391