Puzzles

Why does the following code not work -

package main

import "time"

func worker(input <-chan int, result chan<- int) {
  println("Entered worker")
  for val := range input {
    time.Sleep(time.Second)

    result <- val * 2
  }
  println("Exited worker")
}

func main() {
  input := make(chan int)
  results := make(chan int)

  for range 2 {
    go worker(input, results)
  }

  for i := range 5 {
    input <- i
  }
  close(input)

  for range 5 {
    println(<-results)
  }

}