Pascal's triangle using channels and goroutines

pascal.go

package main

import "fmt"

func worker(row int, input chan int, output chan int, done chan int) {
	display := ""
	previous := 0
	for i := 0; i < row+1; i++ {
		read := <-input
		display += fmt.Sprintf("%d ", read)
		output <- read + previous
		previous = read
	}
	fmt.Println(display)
	output <- 1 // next row has one more element, let's send it
	done <- 1

}

func main() {
	rows := 6
	cmd := make([]chan int, rows+1)
	for i := 0; i < rows+1; i++ {
		cmd[i] = make(chan int, rows+1)
	}
	done := make(chan int, rows)
	cmd[0] <- 1

	for i := 0; i < rows; i++ {
		go worker(i, cmd[i], cmd[i+1], done)
	}

	for i := 0; i < rows; i++ {
		<-done
	}

}