What is the difference between sort(), asort(), and ksort()?

🔹 sort()

• What it does: Sorts an array by values in ascending order.
• Effect on keys: Keys are reset (reindexed) numerically starting from 0.
• Use case: When you only care about values and don’t need original keys.

$fruits = ["d" => "banana", "a" => "apple", "c" => "cherry"];
sort($fruits);
print_r($fruits);

Output:

Array
(
    [0] => apple
    [1] => banana
    [2] => cherry
)

➡ Keys (d, a, c) are lost.

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🔹 asort()

• What it does: Sorts an array by values in ascending order.
• Effect on keys: Keys are preserved.
• Use case: When you want to sort by values but keep the association between keys and values.

$fruits = ["d" => "banana", "a" => "apple", "c" => "cherry"];
asort($fruits);
print_r($fruits);

Output:

Array
(
    [a] => apple
    [d] => banana
    [c] => cherry
)

➡ Keys are preserved.

---

🔹 ksort()

• What it does: Sorts an array by keys in ascending order.
• Effect on values: Values stay tied to their keys.
• Use case: When you want to order an associative array alphabetically or numerically by keys.

$fruits = ["d" => "banana", "a" => "apple", "c" => "cherry"];
ksort($fruits);
print_r($fruits);

Output:

Array
(
    [a] => apple
    [c] => cherry
    [d] => banana
)

➡ Sorted by keys (a, c, d).

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✅ Quick Comparison Table

Function	Sorts by	Keeps Keys?
sort()	Values	❌ No
asort()	Values	✅ Yes
ksort()	Keys	✅ Yes