Online PHP editor | output for WHdDJi

@ 2018-11-26T13:46:07Z

<?php

$array1 = [
 "2018" => 
    [
        "JAN" => 100,
        "FEB" => 200,
        "MAR" => 300,
        "APR" => 400
    ]
];

$array2 = [
 "2018" => 
    [
        "FEB" => 200,
        "MAR" => 300,
        "APR" => 400,
        "MAY" => 200,
    ]
];

$array3 = [
 "2018" => 
    [
        "MAY" => 200,
        "JUN" => 100,
        "JUL" => 300,
        "AUG" => 400,
    ]
];

$new = array_merge_recursive([$array1], [$array2], [$array3]);
foreach($new as $arr){
    foreach($arr as $year => $sub){
        foreach($sub as $month => $val){
            if(!isset($res[$year][$month])) $res[$year][$month] =0;
            $res[$year][$month] += $val;
        }
    }
}
var_dump($res);

Output for 5.6.38, 7.1.0 - 7.1.25, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.28, 8.4.1 - 8.4.14, 8.5.0: array(1) { [2018]=> array(8) { ["JAN"]=> int(100) ["FEB"]=> int(400) ["MAR"]=> int(600) ["APR"]=> int(800) ["MAY"]=> int(400) ["JUN"]=> int(100) ["JUL"]=> int(300) ["AUG"]=> int(400) } }
Output for 8.4.15: /bin/php-8.4.15: /usr/lib/libm.so.6: version `GLIBC_2.38' not found (required by /bin/php-8.4.15) /bin/php-8.4.15: /usr/lib/libm.so.6: version `GLIBC_2.35' not found (required by /bin/php-8.4.15) /bin/php-8.4.15: /usr/lib/libc.so.6: version `GLIBC_2.34' not found (required by /bin/php-8.4.15) /bin/php-8.4.15: /usr/lib/libc.so.6: version `GLIBC_2.38' not found (required by /bin/php-8.4.15)
Process exited with code 1.

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