Reverse String

function reverseStr(str){
    // console.log(str.length)
    var rev = "";
    for(var i = str.length -1; i >= 0; i--){
        // console.log("str.substring(i):", str[i]);
        rev += str[i];
    }
    return rev;
}

function reverse(str){
  if(!str || typeof str != 'string' || str.length < 2 ) return str;
  
  const backwards = [];
  const totalItems = str.length - 1;
  for(let i = totalItems; i >= 0; i--){
    backwards.push(str[i]);
  }
  return backwards.join('');
}

function reverse2(str){
  //check for valid input
  return str.split('').reverse().join('');
}

const reverse3 = str => [...str].reverse().join('');

var text = reverseStr("my name is khan")
console.log(text)