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
+3.2k Javascript : How to loop over and parse JSON data?
+15.7k Golang : Test file read write permission example
+6.1k Golang : Create and shuffle deck of cards example
+13.6k Golang : How to read float value from standard input ?
+4k Unix/Linux : How to fix CentOS yum duplicate glibc or device-mapper-libs dependency error?
+3.7k Swift : Get substring with rangeOfString() function example
+9.9k Golang : Rename directory
+2.9k Google : Block or disable caching of your website content
+7.9k Golang : Simple File Server
+6.7k Golang : Get remaining text such as id or filename after last segment in URL path
+4.8k Golang : Get environment variable
+3.7k PHP : How to handle URI or URL with non-ASCII characters such as Chinese/Japanese/Korean(CJK) ?