making comparison between two or more than two numbers

Hi

I'm writing an algorithm where I need to make comparison between four numbers X, Y, Z, and W to arrange them in a descending order.

Get the numbers X, Y, Z, and W

Make Comparison between X, Y, Z, and W

Show the largest of four

Compare the remaining three numbers

.

.

.

Stop

I have a feeling this is not a correct algorithm. What is your opinion? Could you please help me? First I need to write an algorithm, implementation would be next step. Thanks.