Golang : Roll the dice example
Just a simple example on how to simulate dice rolling. Useful in situation where you need to use random single digit number to ensure different results very time.
UPDATE: The previous code used dice[rand.Intn(len(dice)-1)]
, which caused the dice to never reach the position 6
and also run rand.Seed(time.Now().UnixNano())
multiple times - which is an unnecessary overhead. The code below has been updated to correct the bug and rand.Seed()
function only executes once throughout the duration of this program. Thanks to Patrik Lundin for pointing this out.
Here you go!
package main
import (
"fmt"
"math/rand"
"sync"
"time"
)
var onlyOnce sync.Once
// prepare the dice
var dice = []int{1, 2, 3, 4, 5, 6}
func rollDice() int {
onlyOnce.Do(func() {
rand.Seed(time.Now().UnixNano()) // only run once
})
return dice[rand.Intn(len(dice))]
}
func main() {
dice1 := rollDice()
dice2 := rollDice()
dice3 := rollDice()
fmt.Println("Dice 1: ", dice1)
fmt.Println("Dice 2: ", dice2)
fmt.Println("Dice 3: ", dice3)
}
Sample output:
Dice 1: 6
Dice 2: 2
Dice 3: 2
Dice 1: 5
Dice 2: 1
Dice 3: 3
Happy coding!
Reference:
https://www.socketloop.com/tutorials/golang-how-to-run-your-code-only-once-with-sync-once-object
See also : Golang : Scramble and unscramble text message by randomly replacing words
By Adam Ng
IF you gain some knowledge or the information here solved your programming problem. Please consider donating to the less fortunate or some charities that you like. Apart from donation, planting trees, volunteering or reducing your carbon footprint will be great too.
Advertisement
Tutorials
+10.4k Golang : Surveillance with web camera and OpenCV
+22.1k Golang : minus time with Time.Add() or Time.AddDate() functions to calculate past date
+28.8k Golang : Remove characters from string example
+4.7k Golang : Configure crontab to poll every two minutes 8am to 6pm Monday to Friday
+7.2k Golang : How To Use Panic and Recover
+7.9k Golang : Get SPF and DMARC from email headers to fight spam
+30.6k Golang : Validate email address with regular expression
+18k Golang : Execute shell command
+27.2k Golang : Detect (OS) Operating System
+9k Golang : Get escape characters \u form from unicode characters
+10.6k Golang : How to detect a server/machine network interface capabilities?
+4.5k Golang : Intercept, inject and replay HTTP traffics from web server