console.log(subStrAfterChars('w3resource: JavaScript Exercises', ':'));
console.log(subStrAfterChars('w3resource: JavaScript Exercises', 'E'));
console.log(subStrAfterChars('w3resource: JavaScript Exercises', 'r'));

function subStrAfterChars(str,spc)
{
    var temp =str.split('');
  //   console.log(temp);
    var ar = [];
    
    for(var i =0 ; i<temp.length ; i++)
    {
        if(temp[i] === spc)
        {
            ar.push(temp.slice(i+1,temp.length));
          
            break;
        }
    }
   return ar.join('').replaceAll(',','');
}