var s = "...You...!!!@!3124131212 Hello have this is a --- string Solved !!...? to test @\n\n\n#!#@#@%$**#$@ Congratz this!!!!!!!!!!!!!!!!one ---Problem\n\n";

​

String.prototype.wordAt = function (i) {

  var words = this.split(/[^a-zA-Z0-9]+/);

  if (words.length > 0 && words[0] === '') {

    words.shift();

  }

  if (i-- < 1) return '';

  if (i >= words.length) return '';

  return words[i];

};

​

'12 -1 1 -100 4 1000 9 -1000 16 13 17 15'.split(/\s+/).forEach(function (i) {

  console.log(s.wordAt(i));

});

​