CODE EXAMPLE FOR JAVASCRIPT

first unique character in a string javascript

var firstUniqChar = function(s) {

    for(let i = 0; i < s.length; i++) {
       if( s.indexOf( s.substring(i, i + 1) ) === s.lastIndexOf( s.substring(i, i + 1) ) ) {
           return i
       }
   }

   return -1

};