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<?php // $countAfter[$i][$j] will contain the number of occurrences of a pair $i, $j in the randomly generated sequence $countAfter = [1 => [1 => 0, 2 => 0], 2 => [1 => 0, 2 => 0] ]; $prev = 1; // We assume for simplicify that the "previously" generated value was 1 for ($i = 0; $i < 10000; $i++) { $n = mt_rand(1, 2); $countAfter[$prev][$n]++; $prev = $n; } print_r($countAfter);
Output for 7.3.0
Array ( [1] => Array ( [1] => 2569 [2] => 2497 ) [2] => Array ( [1] => 2496 [2] => 2438 ) )
Output for 7.2.13
Array ( [1] => Array ( [1] => 2618 [2] => 2498 ) [2] => Array ( [1] => 2498 [2] => 2386 ) )
Output for 7.2.12
Array ( [1] => Array ( [1] => 2588 [2] => 2421 ) [2] => Array ( [1] => 2421 [2] => 2570 ) )
Output for 7.2.11
Array ( [1] => Array ( [1] => 2520 [2] => 2532 ) [2] => Array ( [1] => 2532 [2] => 2416 ) )
Output for 7.2.10
Array ( [1] => Array ( [1] => 2443 [2] => 2519 ) [2] => Array ( [1] => 2519 [2] => 2519 ) )
Output for 7.2.9
Array ( [1] => Array ( [1] => 2437 [2] => 2541 ) [2] => Array ( [1] => 2541 [2] => 2481 ) )
Output for 7.2.8
Array ( [1] => Array ( [1] => 2492 [2] => 2487 ) [2] => Array ( [1] => 2487 [2] => 2534 ) )
Output for 7.2.7
Array ( [1] => Array ( [1] => 2545 [2] => 2472 ) [2] => Array ( [1] => 2472 [2] => 2511 ) )
Output for 7.2.6
Array ( [1] => Array ( [1] => 2550 [2] => 2455 ) [2] => Array ( [1] => 2455 [2] => 2540 ) )
Output for 7.2.5
Array ( [1] => Array ( [1] => 2536 [2] => 2504 ) [2] => Array ( [1] => 2504 [2] => 2456 ) )
Output for 7.2.4
Array ( [1] => Array ( [1] => 2527 [2] => 2491 ) [2] => Array ( [1] => 2490 [2] => 2492 ) )
Output for 7.2.3
Array ( [1] => Array ( [1] => 2561 [2] => 2501 ) [2] => Array ( [1] => 2500 [2] => 2438 ) )
Output for 7.2.2
Array ( [1] => Array ( [1] => 2456 [2] => 2531 ) [2] => Array ( [1] => 2531 [2] => 2482 ) )
Output for 7.2.1
Array ( [1] => Array ( [1] => 2524 [2] => 2501 ) [2] => Array ( [1] => 2501 [2] => 2474 ) )
Output for 7.2.0
Array ( [1] => Array ( [1] => 2525 [2] => 2525 ) [2] => Array ( [1] => 2524 [2] => 2426 ) )
Output for 7.1.25
Array ( [1] => Array ( [1] => 2518 [2] => 2514 ) [2] => Array ( [1] => 2514 [2] => 2454 ) )
Output for 7.0.33
Array ( [1] => Array ( [1] => 2472 [2] => 2487 ) [2] => Array ( [1] => 2486 [2] => 2555 ) )
Output for 5.6.38
Array ( [1] => Array ( [1] => 2523 [2] => 2496 ) [2] => Array ( [1] => 2496 [2] => 2485 ) )

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