meet it

Put something new in a box and the old thing is gone.

A box holds one value at a time. Put a new value in and the old one is thrown away. We say you it. Write the type only once, when you first make the box.

You can copy one box into another, like string order = drink;. You can also strings with +, which sticks them end to end, so mind the spaces.

A box can even use its own value. score = score + 1; takes what is in score, adds one and puts the answer back in.

using System;

string drink = "tea";
drink = "coffee";
Console.WriteLine("I would like " + drink);
int score = 5;
score = score + 1;
Console.WriteLine(score);

Write the type again, like int score twice, and C# stops with CS0128, because that name is taken.

guess first

Copy, then change. What will this show?

Guess before you run it. Wrong guesses are how you learn, and nothing is marked.

using System;

string drink = "tea";
string order = drink;
drink = "coffee";
Console.WriteLine(order);

your turn

Your turn. Join a name together.

Type a first name and a last name between the quotes. Then press run and watch + join them, with the spaces in the right places.

Your code

output

press run to see what happens

fix it

You lost a life, but C# will not run. Can you fix it?

Broken code to fix

output

press run to see what happens

Read the error on line 5. C# says the name lives is already defined.
The box was made on line 3. Line 5 only needs to put a new value in it.
Delete the word int at the start of line 5, then press run.

nailed it

your boxes can change now. :D

A new value overwrites the old one.
Write the type only once, when you make the box.
+ joins strings end to end, so mind the spaces.

new words in your collection

overwrite
join

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