Your team is writing a fancy new text editor and you've been tasked with implementing the line numbering.
Write a function which takes a list of strings and returns each line prepended by the correct number.
The numbering starts at 1. The format is n: string. Notice the colon and space in between.
Examples:
number([]) // => []
number(["a", "b", "c"]) // => ["1: a", "2: b", "3: c"]
var number=function(array){
return array.map((d, i) => `${i + 1}: ${d}`);
}