# Lists - Strings

## Objective

After working through this lesson, you’ll be able to

* Write Python code using lists.

## Video Lecture

{% embed url="<https://youtu.be/aOdctNQAeY8>" %}

## Introductory Problem

Create a list of 3 of your friends.  Print the list using a for loop.

{% code title="intro.py" %}

```python
done = False
friends = ["Sofia", "Alex", "Sam"]
while not done:
    print("Menu")
    print("I - Introduction")
    print("Q - Quit")
    choice = input("Choice: ")
    if choice == "I":
        print("Introductory Problem")
        for f in friends:
            print(f)
    elif choice == "Q":
        print("Quitting")
        done = True
```

{% endcode %}

## Examples

### Example 1

You make a new friend named “Chaya” on the bus ride.  Add this friend to the end of the list. Print the list using a for loop.

```python
done = False
friends = ["Sofia", "Alex", "Sam"]
while not done:
    print("Menu")
    print("E1 - Example 1")
    print("Q - Quit")
    choice = input("Choice: ")
    if choice == "E1":
        print("Example 1")
        friends.append("Chaya")
        for pal in friends:
            print(pal)
    elif choice == "Q":
        print("Quitting")
        done = True
```

### Example 2

One of your friends moves away. Ask the user for the friend's name.  Delete this friend. Print the list using a for loop.

```python
done = False
friends = ["Sofia", "Alex", "Sam"]
while not done:
    print("Menu")
    print("E2 - Example 2")
    print("Q - Quit")
    choice = input("Choice: ")
    if choice == "E2":
        print("Example 2")
        friends.pop(0)
        for pal in friends:
            print(pal)
    elif choice == "Q":
        print("Quitting")
        done = True
```

### Example 3

You make new friends riding the bus.  Ask the user for a new friend 3 times.  Using a for loop, print the list of friends.  Print the total number of friends.

```python
done = False
friends = ["Sofia", "Alex", "Sam"]
while not done:
    print("Menu")
    print("E3 - Example 3")
    print("Q - Quit")
    choice = input("Choice: ")
    if choice == "E3":
        print("Example 3")
        for x in range(3):
            name = input("New Friend: ")
            friends.append(name)
        for f in friends:
            print(f)
        print("Number of Friends:",len(friends))
    elif choice == "Q":
        print("Quitting")
        done = True
```

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