04.4.1.md

eBook/examples/chapter_4/random.go

@@ -0,0 +1,28 @@
+package main
+
+import (
+	"fmt"
+	"math/rand"
+	"time"
+)
+
+func main() {
+	for i := 0; i < 10; i++ {
+		a := rand.Int()
+		fmt.Printf("%d / ", a)
+	}
+	for i := 0; i < 5; i++ {
+		r := rand.Intn(8)
+		fmt.Printf("%d / ", r)
+	}
+	fmt.Println()
+	timens := int64(time.Now().Nanosecond())
+	rand.Seed(timens)
+	for i := 0; i < 10; i++ {
+		fmt.Printf("%2.2f / ", 100*rand.Float32())
+	}
+}
+/* Output:
+134020434 / 1597969999 / 1721070109 / 2068675587 / 1237770961 / 220031192 / 2031484958 / 583324308 / 958990240 / 413002649 / 6 / 7 / 2 / 1 / 0 / 
+22.84 / 10.12 / 44.32 / 58.58 / 15.49 / 12.23 / 30.16 / 88.48 / 34.26 / 27.18 / 
+*/