Hoisting VI

Question

What does the code snippet to the right output by console.log?

Snippet

var foo = 1;
(function () {
  console.log(foo);
  foo = 2;
  console.log(window.foo);
  console.log(foo);
  var foo = 3;
  console.log(foo);
  console.log(window.foo)
})()

Source

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