## Why Does My Go Code Generate the Same Random Number Every Time?

Understanding Random Number Generation in Go

In Go, the rand.Intn(n int) int function generates a non-negative pseudo-random number in the range [0, n) from a default shared Source. However, users may encounter situations where this function appears to generate the same random number for every run. This can occur if the default Source is not properly seeded.

Default Behavior and Seeding

The documentation for the rand package states that if rand.Seed() is not explicitly called, the default Source is seeded with the value 1. This means that the random number generator behaves deterministically and produces the same sequence of values for every run.

Proper Seeding for True Randomness

To ensure true randomness, it is recommended to call rand.Seed() with a random seed value. A common approach is to use the current Unix timestamp, as seen in the following example:

<code class="go">rand.Seed(time.Now().UnixNano())</code>

By calling rand.Seed() with a constantly changing value, such as the Unix timestamp, the default Source is initialized to a different deterministic state for each run. This results in the generation of genuinely random numbers.

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