From d6b1144ac0423b86666510117a6e69bd64ba2970 Mon Sep 17 00:00:00 2001
From: Junwei Zhao <wahyd4@gmail.com>
Date: Tue, 23 Apr 2019 15:52:42 +1000
Subject: [PATCH] add goroutine

---
 main.go | 48 +++++++++++++++++++++++++++++++++++-------------
 1 file changed, 35 insertions(+), 13 deletions(-)

diff --git a/main.go b/main.go
index 3eb442d..5a4e336 100644
--- a/main.go
+++ b/main.go
@@ -4,7 +4,9 @@ import (
 	"flag"
 	"fmt"
 	"math/rand"
+	"runtime"
 	"sort"
+	"sync"
 	"time"
 )
 
@@ -12,13 +14,16 @@ import (
 const (
 	NumberCount    = 7
 	MaximumResults = 50
+	Routines       = 10
 )
 
 var (
-	winners = make(map[[NumberCount]int]int)
+	syncWinners sync.Map
+	signals     = make(chan bool, Routines)
 )
 
 func main() {
+	runtime.GOMAXPROCS(runtime.NumCPU())
 	timesInput := flag.Int("t", 100000, "an int")
 	flag.Parse()
 	times := *timesInput
@@ -28,12 +33,27 @@ func main() {
 	startTime := now.Unix()
 
 	fmt.Printf("Started at %v to run lottery for %v times \n", now, times)
-	for i := 0; i < times; i++ {
-		winner := run()
-		if currentTimes, ok := winners[winner]; ok {
-			winners[winner] = currentTimes + 1
-		} else {
-			winners[winner] = 1
+	for routine := 0; routine < Routines; routine++ {
+		go func() {
+			for i := 0; i < times/Routines; i++ {
+				winner := run()
+				if currentTimes, ok := syncWinners.Load(winner); ok {
+					currentTimesInt := currentTimes.(int)
+					syncWinners.Store(winner, currentTimesInt+1)
+				} else {
+					syncWinners.Store(winner, 1)
+				}
+			}
+			signals <- true
+		}()
+	}
+
+	routineReturnTimes := 0
+	for range signals {
+		routineReturnTimes++
+		fmt.Println(routineReturnTimes)
+		if routineReturnTimes == Routines {
+			close(signals)
 		}
 	}
 
@@ -45,13 +65,15 @@ func main() {
 	}
 
 	var ss []kv
-	for k, v := range winners {
-		// to reduce the time consuming, if the number only exists once then skip it
-		if v > 1 {
-			ss = append(ss, kv{k, v})
-		}
 
-	}
+	syncWinners.Range(func(key interface{}, value interface{}) bool {
+		winningTimes := value.(int)
+		winningNumber := key.([7]int)
+		if winningTimes > 1 {
+			ss = append(ss, kv{winningNumber, winningTimes})
+		}
+		return true
+	})
 
 	sort.Slice(ss, func(i, j int) bool {
 		return ss[i].Value > ss[j].Value