first

course/13-channels/exercises/5-close/complete.go

@@ -0,0 +1,47 @@
+package main
+
+import (
+	"fmt"
+	"time"
+)
+
+func countReports(numSentCh chan int) int {
+	total := 0
+	for {
+		numSent, ok := <-numSentCh
+		if !ok {
+			break
+		}
+		total += numSent
+	}
+	return total
+}
+
+// TEST SUITE - Don't touch below this line
+
+func test(numBatches int) {
+	numSentCh := make(chan int)
+	go sendReports(numBatches, numSentCh)
+
+	fmt.Println("Start counting...")
+	numReports := countReports(numSentCh)
+	fmt.Printf("%v reports sent!\n", numReports)
+	fmt.Println("========================")
+}
+
+func main() {
+	test(3)
+	test(4)
+	test(5)
+	test(6)
+}
+
+func sendReports(numBatches int, ch chan int) {
+	for i := 0; i < numBatches; i++ {
+		numReports := i*23 + 32%17
+		ch <- numReports
+		fmt.Printf("Sent batch of %v reports\n", numReports)
+		time.Sleep(time.Millisecond * 100)
+	}
+	close(ch)
+}