Efficiently move the engine ahead by 2^128 steps

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- PHP Manual
- Random\Engine\Xoshiro256StarStar
- Efficiently move the engine ahead by 2^128 steps

# Random\Engine\Xoshiro256StarStar::jump

(PHP 8 >= 8.2.0)

Random\Engine\Xoshiro256StarStar::jump — Efficiently move the engine ahead by 2^128 steps

### Description

public Random\Engine\Xoshiro256StarStar::jump(): void

Moves the algorithm’s state ahead by 2128 steps, as if Random\Engine\Xoshiro256StarStar::generate() was called 2128 times.

The purpose of a jump is to facilitate the creation of a new Random\Engine\Xoshiro256StarStar engine from an existing seeded Random\Engine\Xoshiro256StarStar engine. The seeded engine acts as a blueprint, which can be cloned and repeatedly jumped to create 2128 non-overlapping sequences with 2128 values each.

### Parameters

This function has no parameters.

### Return Values

No value is returned.

### Examples

Example #1 Random\Engine\Xoshiro256StarStar::jump() example

    <?php
    use Random\Engine\Xoshiro256StarStar;
    use Random\Randomizer;

    $blueprintRng = new Xoshiro256StarStar(0);

    $fibers = [];
    for ($i = 0; $i < 8; $i++) {
        $fiberRng = clone $blueprintRng;
        $blueprintRng->jump();

        $fiber = new Fiber(static function () use ($fiberRng, $i): void {
            $randomizer = new Randomizer($fiberRng);

            while (true) {
                Fiber::suspend();

                echo "{$i}: ", $randomizer->getInt(0, 100), "\n";
            }
        });
        $fiber->start();

        $fibers[] = $fiber;
    }

    // Even though the fibers execute in a random order, they will print the same value
    // each time, because each has its own unique instance of the RNG.
    $randomizer = new Randomizer();

    $fibers = $randomizer->shuffleArray($fibers);
    foreach ($fibers as $fiber) {
        $fiber->resume();
    }

    $fibers = $randomizer->shuffleArray($fibers);
    foreach ($fibers as $fiber) {
        $fiber->resume();
    }
    ?>

The above example will output something similar to:

    4: 89
    3: 10
    2: 63
    1: 75
    6: 41
    5: 56
    0: 16
    7: 60
    7: 34
    6: 58
    1: 74
    4: 63
    3: 3
    5: 42
    2: 45
    0: 86

### See Also

- Random\Engine\Xoshiro256StarStar::jumpLong() - Efficiently move the engine ahead by 2^192 steps