var r = undefined;
a = b = c = 20;
n = i = r;

for(i = 0; i < n; i++){
  b = i;
}

var x = 0;

function multiply(a, b){
  var x = a * b;
  return x;
}

var z = multiply(20, 10);

(function(){
  b = 20;
  var a = 10 * b;
})();

a = 10;
a /= 2;

var a = { bar: 10, baz: 20, foo: 40 };
a.foo += a.bar;

var a = "I ran all the way home";

var b = "I ran all the way home".split(' ');

var m = /test/.test("I know this is a test");

Object.prototype.mush = function(){
  var b = 0, c = [];
  if(this instanceof Array){
    b = this.reduce(function(s,i){ return s + i; });
    c = this.map(function(i){ return b; });
  }
  return c;
}

a = [1,2,3,4,5,6,7];

a.mush();

b = a[2];