Backend

package main



import (

  "fmt"

)



func main() {

  naturals := make(chan int)

  squares := make(chan int)



  go func() {

    for x := 0; x <= 10; x++ {

      naturals <- x

    }

    close(naturals)

  }()



  go func() {

    for x := range naturals {

      squares <- x * x

    }

    close(squares)

  }()



  for x := range squares {

    fmt.Println(x)

  }

}