Question

How to generate 20 digits random number in Go

Answer 1

package main
 
import (
    "fmt"
    "math/rand"
    "time"
    "reflect"
    "strconv"
)
 
func main() {
    rand.Seed(time.Now().UnixNano())
     
    var number string
    for i := 0; i < 20; i++ {
        digit := rand.Intn(9 + 1 - 1) + 1 // generates a random digit between 1 and 9
        //digit := rand.IntN(max + 1 - min) + min
        number += fmt.Sprintf("%d", digit)
    }
     
    n, err := strconv.ParseFloat(number, 64)
    if err != nil {
        panic(err)
    }
     
    fmt.Println(number)
    fmt.Printf("%v type = %s\n", n, reflect.TypeOf(n))
}
 
 

/*
run:
 
84513592544473697963
8.45135925444737e+19 type = float64
 
*/

 

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