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Mastering Concurrency in Go

Solution Review: Multiplication Table

Understand the use of WaitGroup to manage concurrency in Go by reviewing a multiplication table example. Learn how goroutines are launched, synchronized, and coordinated to ensure ordered output, helping you grasp key concurrency patterns in practical coding.

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Here is the code to the challenge in the previous lesson:

Go (1.6.2)
package main
import ( "fmt"
          "sync"
          "time")
          
func printTable(n int, wg *sync.WaitGroup) {
  for i := 1; i <= 12; i++ {
    fmt.Printf("%d x %d = %d\n", i, n, n*i)
    time.Sleep(50 * time.Millisecond)
  }
  wg.Done()
}
func main() {
  var wg sync.WaitGroup
  
  for number := 2; number <= 12; number++ {
    wg.Add(1)
    go printTable(number,&wg)
  }
  wg.Wait()
}

So we added a WaitGroup from the sync package on line 15 named wg. At every iteration in the for-loop in the main routine, we increment the counter of wg on line 18. In the next step on line 19, we execute the ...