text: 'use strict';
  
  String.prototype.count = function (s1) {
  
      return (this.length - this.replace(new RegExp(s1, "g"), '').length) / s1.length;
  };
  
  String.prototype.repeat = function (n) {
    n = n || 1;
  
    return Array(n + 1).join(this);
  };
  
  String.prototype.reverse = function () {
  
      return this.split("").reverse().join("");
  };
  