Python Coding Challenge - Question with Answer (ID -141225)

 

Key Idea (Very Important )

• The for x in a loop iterates over the original elements of the list, not the updated ones.

• Changing a[0] does not affect the sequence of values that x will take.

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Step-by-step Execution

Initial values:

a = [1, 2, 3, 4]
total = 0

Iteration 1

x = 1 

total = 0 + 1 = 1 

a[0] = 1

a = [1, 2, 3, 4]

Iteration 2

x = 2 

total = 1 + 2 = 3 

a[0] = 3

a = [3, 2, 3, 4]

Iteration 3

x = 3 

total = 3 + 3 = 6 

a[0] = 6

a = [6, 2, 3, 4]

Iteration 4

x = 4 

total = 6 + 4 = 10 

a[0] = 10

a = [10, 2, 3, 4]

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Final Output

[10, 2, 3, 4]

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 Takeaway

• Modifying a list inside a for loop does not change the iteration values.

• The loop uses an internal index to fetch the next element.

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