[자바스크립트로 구현한 알고리즘] Credit Card Mask

Description:

Usually when you buy something, you're asked whether your credit card number, phone number or answer to your most secret question is still correct.

However, since someone could look over your shoulder, you don't want that shown on your screen. Instead, we mask it. Your task is to write a function maskify, which changes all but the last four characters into '#'.

 

Examples

 

maskify("4556364607935616") == "############5616"

maskify( "64607935616") == "#######5616"

maskify( "1") == "1"

maskify( "") == ""

// "What was the name of your first pet?"

maskify("Skippy") == "##ippy"

maskify("Nananananananananananananananana Batman!") == "####################################man!"

아래는 개선된 코드입니다.