Pls I need an explanation to this code..

Question

Var str = "js css html php";
Var res1 = str.substring(-2,2);
Var res2 = str.substr(-3,3);
Var res3 = str.slice(-3);
Console.log(res1 + " " + res2 + " " + res3)
Answer= js php php
How??
What I did..
res1= css html ph
res 2= l p
res3 = Js css html p

Answer 1

Ipang Thanks so much

Answer 2

`substring` method and `substr` method works in different ways, and so does `slice` method.

Output in console:
"js php php"

+ About substring method
<res1> is result from `substring` method, and - as quoted from https://www.w3schools.com/jsref/jsref_substring.asp where it says ...

"If either "start" or "end" is less than 0, it is treated as if it were 0."

+ About `substr` method
https://www.w3schools.com/jsref/jsref_substr.asp

+ About `slice` method
https://www.w3schools.com/jsref/jsref_slice_string.asp