Given var fruits = ["apple": 4, "banana": 6], how can you safely add 1 to the count of "pear", initializing it if it doesn't exist?

hard📝 Application Q8 of 15

Swift - Collections

Given var fruits = ["apple": 4, "banana": 6], how can you safely add 1 to the count of "pear", initializing it if it doesn't exist?

Afruits.updateValue(fruits["pear"]! + 1, forKey: "pear")

Bfruits["pear", default: 0] += 1

Cfruits["pear"] = fruits["pear"]! + 1

Dfruits["pear"] = fruits["pear"] ?? 1

Step-by-Step Solution

Solution:

Step 1: Use dictionary subscripting with default
To safely increment a value for a key that might not exist, use fruits["pear", default: 0] which returns 0 if "pear" is missing.
Step 2: Increment the value
Adding 1 to this defaulted value updates the dictionary correctly.
Step 3: Analyze other options
fruits.updateValue(fruits["pear"]! + 1, forKey: "pear") and C force unwrap optional values which can cause runtime errors if the key is missing. fruits["pear"] = fruits["pear"] ?? 1 sets the value to 1 if missing but does not increment existing values.
Final Answer:
fruits["pear", default: 0] += 1 -> Option B
Quick Check:
Check safe increment with default subscript [OK]

Quick Trick: Use dict[key, default: 0] += 1 to safely increment [OK]

Common Mistakes:

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