Question

Compute the alternating sum of all elements in a list. For example, if your program

reads the input then it computes

1 4 9 16 9 7 4 9 11

1 – 4 + 9 – 16 + 9 – 7 + 4 – 9 + 11 = –2

In python, the output given is just an example.

Answer 1

                       ANSWER : HERE IS THE ANSWER FOR YOUR QUESTION:

  

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        CODE:

no=int(input("How many elements in the list:"))

l=[]

for i in range(no):
#appending the element in the list
ele=int(input("Enter element in list:"))
#when the index is even , we add the same value in the list
if i%2==0:
l.append(ele)
#when the index is odd , we add the negative of the value in the list
else:
l.append(-ele)
  

#finally , we print the sum of the element in the list using sum function
print("the alternating sum of the element in the list is: ",sum(l))
  
  
  

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                  SNIPPET

main.py 1 2 no=int(input("How many elements in the list:")) 3 4 1=[] 8 10 5 6- for i in range(no): 7 #appending the element in the list ele-int(input("Enter element in list:")) 9 #when the index is even , we add the same value in the list if i%2==0; 11 1.append(ele) 12 #when the index is odd, we add the negative of the value in the list 13 else: 14 1.append(-ele) 15 16 17 #finally, we print the sum of the element in the list using sum function 18 print("the alternating sum of the element in the list is: ", sum(1)) 19 20

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                  OUTPUT

How many elements in the list:6 Enter element in list:34 Enter element in list:34 Enter element in list:56 Enter element in list:56 Enter element in list:43 Enter element in list:42 the alternating sum of the element in the list is: 1

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