Javascript Array numberOfOccurrences(el)

// The numberOfOccurrences function must return the number of occurrences of an element in an array.

// var arr = [0,1,2,2,3];
// arr.numberOfOccurrences(0) === 1;
// arr.numberOfOccurrences(4) === 0;
// arr.numberOfOccurrences(2) === 2;
// arr.numberOfOccurrences("a") === 0;

Array.prototype.numberOfOccurrences = function (el) {
  var count = 0;/*  www.j av  a  2 s  .  c o m*/
  this.forEach(function (item) {
    if (item === el) count++;
  });
  return count;
}