Intn in Go
Intn returns, as an int, a non-negative pseudo-random number in [0,n) from the default Source. It panics if n <= 0.
package main
import (
"fmt"
"math/rand"
)
func main() {
// Seeding with the same value results in the same random sequence each run.
// For different numbers, seed with a different value, such as
// time.Now().UnixNano(), which yields a constantly-changing number.
rand.Seed(86)
fmt.Println(rand.Intn(100))
fmt.Println(rand.Intn(100))
fmt.Println(rand.Intn(100))
}