Write a program to check if a number is present in the list or not. If the number is present, print the position of the number. Print an appropriate message if the number is not present in the list.

Question

Accepted Answer

> [!TLDR]
> Test membership first with `in`, and only then ask for the location with `index()`. `num in myList` answers "is it there?"; `myList.index(num)` answers "where?" — calling `index()` on an absent value crashes with `ValueError`, which is exactly why the `in` check comes first.

**The idea.** Python gives us two purpose-built tools: the membership operator `in` (returns `True`/`False`) and the list method `index()` (returns the first index of a value). The safe pattern is *check, then locate*.

```python
myList = [17, 23, 4, 91, 55, 8]
num = int(input("Enter the number to search: "))

if num in myList:
    print(num, "is present at position", myList.index(num) + 1)
else:
    print(num, "is not present in the list")
```

**Two sample runs:**

```text
Enter the number to search: 91
91 is present at position 4
```

```text
Enter the number to search: 50
50 is not present in the list
```

**Why the key lines work**

- `if num in myList:` — the `in` operator scans the list and returns `True` the moment it finds a match. It is the cleanest way to ask "is this element present?". …

Q.Write a program to check if a number is present in the list or not. If the number is present, print the position of the number. Print an appropriate message if the number is not present in the list.

Concept understanding — List Operations

Q.Write a program to check if a number is present in the list or not. If the number is present, print the position of the number. Print an appropriate message if the number is not present in the list.

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