How to quickly determine differences in a string?

Question

JavaScript

There are two lines:
1. Hello
2. He_ll_o
How to determine where the words differ (character number)? What are fast algorithms?

Answer 1

https://github.com/kpdecker/jsdiff

Answer 2

write a loop and check the correctness and compliance of the character through indexOf ()

Answer 3

Fuzzy search, materiel Fuzzy search in text and dictionary

Answer 4

Levenshtein distance

Answer 5

function compare(a,b) {
 if(a==b) return 0;
 var m=Math.min(a.length,b.length);
 var r=m+1;
 if (m>0) {
  for (var i=0;i<m;i++) 
    if (a[i]!=b[i]) {
         r=i+1;
         break;
    }
 } else r=1;
 return r;
}

var a='Hello';
var b='He_ll_o';

document.write(compare(a,b)); //3