Flat array or assoc array

flat-or-assoc.php

<?php

$try_count = 50000000;

$t0 = microtime(true);

for ($i = 0; $i < $try_count; $i++) {
    $data1 = [
        'EU', 'AD', 'AL', 'AT', 'BA', 'BE', 'BG', 'BY',
        'CH', 'CS', 'CZ', 'DE', 'DK', 'EE', 'ES', 'FI',
        'FO', 'FR', 'FX', 'GB', 'GI', 'GR', 'HR', 'HU',
        'IE', 'IS', 'IT', 'LI', 'LT', 'LU', 'LV', 'MC',
        'MD', 'MK', 'MT', 'NL', 'NO', 'PL', 'PT', 'RO',
        'SE', 'SI', 'SJ', 'SK', 'SM', 'UA', 'VA'
    ];
}

$t1 = microtime(true);

for ($i = 0; $i < $try_count; $i++) {
    $data2 = [
        'EU' => true,
        'AD' => true,
        'AL' => true,
        'AT' => true,
        'BA' => true,
        'BE' => true,
        'BG' => true,
        'BY' => true,
        'CH' => true,
        'CS' => true,
        'CZ' => true,
        'DE' => true,
        'DK' => true,
        'EE' => true,
        'ES' => true,
        'FI' => true,
        'FO' => true,
        'FR' => true,
        'FX' => true,
        'GB' => true,
        'GI' => true,
        'GR' => true,
        'HR' => true,
        'HU' => true,
        'IE' => true,
        'IS' => true,
        'IT' => true,
        'LI' => true,
        'LT' => true,
        'LU' => true,
        'LV' => true,
        'MC' => true,
        'MD' => true,
        'MK' => true,
        'MT' => true,
        'NL' => true,
        'NO' => true,
        'PL' => true,
        'PT' => true,
        'RO' => true,
        'SE' => true,
        'SI' => true,
        'SJ' => true,
        'SK' => true,
        'SM' => true,
        'UA' => true,
        'VA' => true,
    ];
}

$t2 = microtime(true);

$create_simple_array = $t1 - $t0;
$create_assoc_array = $t2 - $t1;

echo "--> Array declaration after {$try_count} times:\n";
printf("Simple array: %f sec\n", $create_simple_array);
printf("Assoc array: %f sec\n", $create_assoc_array);


$data1 = [
    'EU', 'AD', 'AL', 'AT', 'BA', 'BE', 'BG', 'BY',
    'CH', 'CS', 'CZ', 'DE', 'DK', 'EE', 'ES', 'FI',
    'FO', 'FR', 'FX', 'GB', 'GI', 'GR', 'HR', 'HU',
    'IE', 'IS', 'IT', 'LI', 'LT', 'LU', 'LV', 'MC',
    'MD', 'MK', 'MT', 'NL', 'NO', 'PL', 'PT', 'RO',
    'SE', 'SI', 'SJ', 'SK', 'SM', 'UA', 'VA'
];
$data2 = [
    'EU' => true,
    'AD' => true,
    'AL' => true,
    'AT' => true,
    'BA' => true,
    'BE' => true,
    'BG' => true,
    'BY' => true,
    'CH' => true,
    'CS' => true,
    'CZ' => true,
    'DE' => true,
    'DK' => true,
    'EE' => true,
    'ES' => true,
    'FI' => true,
    'FO' => true,
    'FR' => true,
    'FX' => true,
    'GB' => true,
    'GI' => true,
    'GR' => true,
    'HR' => true,
    'HU' => true,
    'IE' => true,
    'IS' => true,
    'IT' => true,
    'LI' => true,
    'LT' => true,
    'LU' => true,
    'LV' => true,
    'MC' => true,
    'MD' => true,
    'MK' => true,
    'MT' => true,
    'NL' => true,
    'NO' => true,
    'PL' => true,
    'PT' => true,
    'RO' => true,
    'SE' => true,
    'SI' => true,
    'SJ' => true,
    'SK' => true,
    'SM' => true,
    'UA' => true,
    'VA' => true,
];

$t0 = microtime(true);

for ($i = 0; $i < $try_count; $i++) {
    in_array('hoge', $data1);
}

$t1 = microtime(true);

for ($i = 0; $i < $try_count; $i++) {
    array_key_exists('hoge', $data2);
}

$t2 = microtime(true);

$search_simple_array = $t1 - $t0;
$search_assoc_array = $t2 - $t1;

echo "--> Array key search after {$try_count} times:\n";
printf("Simple array: %f sec\n", $search_simple_array);
printf("Assoc array: %f sec\n", $search_assoc_array);

echo "--> Total after {$try_count} times:\n";
printf("Simple array: %f sec\n", $create_simple_array + $search_simple_array);
printf("Assoc array: %f sec\n", $create_assoc_array + $search_assoc_array);

/*
--> Array declaration after 50000000 times:
Simple array: 10.235229 sec
Assoc array: 12.065151 sec
--> Array key search after 50000000 times:
Simple array: 3.945283 sec
Assoc array: 1.502123 sec
--> Total after 50000000 times:
Simple array: 14.180512 sec
Assoc array: 13.567274 sec
*/

% php -v
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