[Solved] What will happen if you run this Swift code?var numbers = [1, 2, 3] for number in numbers { numbers.append(number + 3) print(number) } | Swift

Swift - Loops

What will happen if you run this Swift code?

var numbers = [1, 2, 3]
for number in numbers {
  numbers.append(number + 3)
  print(number)
}

AInfinite loop printing numbers

BPrints 1 2 3 and then stops

CCompile-time error due to modifying collection during iteration

DRuntime crash due to array modification

Step-by-Step Solution

Solution:

Step 1: Identify mutation inside loop
The code tries to append to 'numbers' while looping over it.
Step 2: Recall Swift safety rules
Swift disallows modifying a collection during iteration and shows a compile-time error.
Final Answer:
Compile-time error due to modifying collection during iteration -> Option C
Quick Check:
Modifying collection in loop = Compile-time error [OK]

Quick Trick: Cannot change collection while looping in Swift [OK]

Common Mistakes:

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