Question

How to find all repeating characters in a string with JavaScript

Answer 1

function GetAllRepeatingCharacters(str) {
 	const repeating = {};
 	
    for (const ch of str) {
        repeating[ch] = (repeating[ch] || 0) + 1;
    }
    
    return Object.entries(repeating).filter(ch => ch[1] > 1).map(ch => ch[0]);
}

const s = "java c c++ csharp javascript php python";

console.log(GetAllRepeatingCharacters(s)); 

  
  
  
  
/*
run:
  
["j", "a", "v", " ", "c", "+", "s", "h", "r", "p", "t"]
  
*/

 

70+ SQL courses for beginners and professionals