Go language provides inbuilt support for generating random numbers of the specified type with the help of a math/rand package. This package implements pseudo-random number generators. These random numbers are generated by a source and this source produces a deterministic sequence of values every time when the program run. And if you want to random numbers for security-sensitive work, then use the crypto/rand package.
You are allowed to generate a non-negative pseudo-random number in [0, n) of 31-bit integer n as an int32 type from the default source with the help of the Int31n() function provided by the math/rand package. So, you need to add a math/rand package in your program with the help of the import keyword to access the Int31() function. This method will panic if the value of n is <= 0.
func Int31n(n int32) int32
Let us discuss this concept with the help of the given examples:
Random Number 1: 1 Random Number 2: 3 Random Number 3: 0
panic: invalid argument to Int31n
goroutine 1 [running]:
math/rand.(*Rand).Int31n(0x43e280, 0x0, 0x43e280, 0x460000)