golang QQ:29295842 欢迎技术交流go语言返回1-99之间随机数的方法
package mainimport ("fmt""math/rand")func main() {max := big.NewInt(100)i, err := rand.Int(rand.Reader, max)}
随机数
package mainimport "fmt"import "math/rand"func main() {//例如，rand.Intn 返回一个随机的整数 n，0 <= n <= 100。fmt.Print(rand.Intn(100), ",")fmt.Print(rand.Intn(100))fmt.Println()//rand.Float64 返回一个64位浮点数 f，0.0 <= f <= 1.0。 fmt.Println(rand.Float64())//这个技巧可以用来生成其他范围的随机浮点数，例如5.0 <= f <= 10.0fmt.Print((rand.Float64()*5)+5, ",")fmt.Print((rand.Float64() * 5) + 5)fmt.Println()//要让伪随机数生成器有确定性，可以给它一个明确的种子。s1 := rand.NewSource(42)r1 := rand.New(s1)//调用上面返回的 rand.Source 的函数和调用 rand 包中函数是相同的。fmt.Print(r1.Intn(100), ",")fmt.Print(r1.Intn(100))fmt.Println()如果使用相同的种子生成的随机数生成器，将会产生相同的随机数序列。s2 := rand.NewSource(42)r2 := rand.New(s2)fmt.Print(r2.Intn(100), ",")fmt.Print(r2.Intn(100))fmt.Println()}$ go run random-numbers.go 81,870.66456005321849047.123187485356329,8.4341153643355475,875,87
生成随机数的方法
package main import ( "fmt" "time" "math/rand") func main() { r := rand.New(rand.NewSource(time.Now().UnixNano())) for i:=0; i<10; i++ { fmt.Println(r.Intn(100)) }}
产生不重复的随机数
package utilsimport ("math/rand""time")var channel chan int64 = make(chan int64, 32)func init() {go func() {var old int64for {o := rand.New(rand.NewSource(time.Now().UnixNano())).Int63()if old != o {old = oselect {case channel <- o:}}}}()}func RandInt64() (r int64) {select {case rand := <-channel:r = rand}return}
随机生成验证码
/*** size 随机码的位数* kind 0 // 纯数字1 // 小写字母2 // 大写字母3 // 数字、大小写字母*/func krand(size int, kind int) []byte {ikind, kinds, result := kind, [][]int{[]int{10, 48}, []int{26, 97}, []int{26, 65}}, make([]byte, size)is_all := kind > 2 || kind < 0rand.Seed(time.Now().UnixNano())for i := 0; i < size; i++ {if is_all { // random ikindikind = rand.Intn(3)}scope, base := kinds[ikind][0], kinds[ikind][1]result[i] = uint8(base + rand.Intn(scope))}return result}
