understand priorities of queues in NodeJS

Guess the output!!

console.log('1');

setImmediate(() => {
  console.log('3');
});

setTimeout(() => {
  console.log('4');
}, 0);

process.nextTick(() => {
  console.log('2');
});

OUTPUT:

1
2
4
3

Guess How?? (Try to run the code here.)

Output depends on the priorities of different queues involves in the execution.

Priority of [ process.nextTick() > Timer Queue (setTimeout) > Check Queue (setImmediate) ]

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