Menene Recursion?

Question

Menene Recursion?

Accepted Answer

**Recursion** shine lokaci wanda aiki ya kira kanta don magance karami ɗan yadda ra'ayinta ta jiya. Kowane recursion yana bukatar **tsarin gida** wanda ke tsayewa da **halin recursion** wanda ke tafiya zuwa gida.

## Ƙwaƙwalwar

Kata matsala ta zuwa ƙananan matsaloli daidai suke. Kowane kira ana tutshi kiram kan **call stack**; komawa suke burga su.

## Misali

```python
def factorial(n):
    if n <= 1:            # base case: stop recursing
        return 1
    return n * factorial(n - 1)   # recursive case: smaller problem

factorial(4)             # 4 * 3 * 2 * 1 -> 24
```

## Bakin

```text
factorial(4)
= 4 * factorial(3)
= 4 * (3 * factorial(2))
= 4 * (3 * (2 * factorial(1)))
= 4 * 3 * 2 * 1 = 24
```

## Haɗin gida

Han ne **O(n)** lokaci da **O(n)** sararin samaniya (kiram gida ɗaya ɗo kiram ɗo).

## Damuwowa

- **Tsarin gida ba a shi ba** -> recursion ba siyata -> call stack overflow.
- Malallin recursion zai iya kashe stack; wasu harsuna ba su da haɗi na karshen kira.
- Sake ƙididdige matsaloli masu lamba na gida zai iya yadda zuwa lokacin ɗimbin hanyar (gyara tare da mnemonic).

## Me ya sa aka damje shi

Recursion yana magana ta jiya matsalolin da suke kama da kansu — bishiyoyi, gida-gida, raba da ƙarfi — kyau fiye da loops.

Shi ne tunani na gida dakin bayan merge sort, backtracking, da dynamic programming.

Tunanin call stack kuma yana ba ka sauyi iyakancewa da tunani game da alaƙa.