Indexes in Array.map()

Here's a tougher one: use map to update a list of numbers like so:

• the first number should be unchanged
• the second number should be increased by one
• the third number should be increased by two
• the fourth number should be increased by three -- and so on...

It's easy enough to create a function that will always add one...

const nums = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
const result = nums.map((num) => num + 1);

But now we want to add a different number to each element depending on the number's position in the array.

Can you do it?

Hint

It will help to know that when map calls the function you provide, it passes the function three arguments:

• the current element
• the index of the element <-- BIG HINT
• the whole array

Now if only you could use that index to decide how much to add...