What is the difference between map and reduce in programming?

What is the difference between map and reduce in programming?

The 'map' function applies a given function to each item in a list, returning a new list. 'Reduce' takes a function and a list and reduces it to a single value by applying the function cumulatively.

Can you give me an example of how to use map?

Sure! If you have a list of numbers and you want to square each number, you can use map like this: map(lambda x: x**2, [1, 2, 3, 4]) which returns [1, 4, 9, 16].

And how about reduce?

For reduce, if you want to sum a list of numbers, you can do: from functools import reduce; reduce(lambda x, y: x + y, [1, 2, 3, 4]) which returns 10.

When should I use map and when should I use reduce?

Use map when you want to transform each item in a collection, and use reduce when you want to combine items into a single value.