Merge Array

How to combine two sorted arrays into one? We can do this easily with the spread operator.

a1 = [1, 2, 5, 6, 9];
a2 = [3, 4, 7, 8, 10];

res = [...a1, ...a2]; // [1, 2, 5, 6, 9, 3, 4, 7, 8, 10]

But if we want to combine and sort? Again, nothing complicated!

res = [...a1, ...a2].sort((a, b) => +a > +b); // [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

Getting the last element of a split string array

Reversing an array in JS is really simple with the standard array method. Like below