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Shubham Singh Kshatriya

Go provides a built-in package named `math/rand`

to generate pseudorandom numbers.

The **pseudorandom numbers** are a deterministic sequence of numbers that depend on a `seed`

value. In order to generate random numbers on every execution, we need to set the seed every time.

Note: You can learn more about seed here.

In this shot, we’ll see how to generate a random number in a given range using the `rand.Intn()`

function of the `math/rand`

package.

`rand.Intn()`

function```
rand.Intn(n)
```

The ** rand.Intn() function** accepts a number

`n`

and returns an unsigned pseudorandom integer in the interval `[0, n)`

. It will throw an error if the value of `n`

is less than zero.We can use the following syntax to generate a random number in a specific range.

```
rand.Intn(max-min) + min
```

Here, `max`

is the upper bound and `min`

is the lower bound. It will return a random number in the interval `[min, max)`

.

Let’s see an example to generate a random number between 1 and 5.

We will use the following packages.

`fmt`

formats the output.`math/rand`

generates random numbers.`time`

sets the seed.

package main import ( "fmt" "math/rand" "time" ) func main() { min := 1 max := 5 // set seed rand.Seed(time.Now().UnixNano()) // generate random number and print on console fmt.Println(rand.Intn(max - min) + min) }

**Lines 3–7**: We import all the necessary packages.**Lines 10–11**: We declare 2 variables`min`

and`max`

that specify the lower and the upper bound respectively.**Line 13**: We set a seed using`time.Now().UnixNano()`

function. This function will return the number of seconds passed from January 1, 1970.**Line 15**: We generate the random number using the`rand.Intn()`

function and output it on the console.

RELATED TAGS

golang

go

random

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