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exercise1.go
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exercise1.go
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// All material is licensed under the Apache License Version 2.0, January 2004
// http://www.apache.org/licenses/LICENSE-2.0
// Create a program that declares two anonymous functions. One that counts up to
// 100 from 0 and one that counts down to 0 from 100. Display each number with an
// unique identifier for each goroutine. Then create goroutines from these functions
// and don't let main return until the goroutines complete.
//
// Run the program in parallel.
package main
import (
"fmt"
"runtime"
"sync"
)
func init() {
// Allocate one logical processor for the scheduler to use.
runtime.GOMAXPROCS(1)
}
func main() {
// Declare a wait group and set the count to two.
var wg sync.WaitGroup
wg.Add(2)
fmt.Println("Start Goroutines")
// Declare an anonymous function and create a goroutine.
go func() {
// Count down from 100 to 0.
for count := 100; count >= 0; count-- {
fmt.Printf("[A:%d]\n", count)
}
// Tell main we are done.
wg.Done()
}()
// Declare an anonymous function and create a goroutine.
go func() {
// Count up from 0 to 100.
for count := 0; count < 100; count++ {
fmt.Printf("[B:%d]\n", count)
}
// Tell main we are done.
wg.Done()
}()
// Wait for the goroutines to finish.
fmt.Println("Waiting To Finish")
wg.Wait()
fmt.Println("\nTerminating Program")
}