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<?php $a = ['a1','a2','a3','a4']; $b = ['b1','b2','b3','b4']; $c = ['c1','c2','c3','c4']; $all = [ $a, $b, $c ]; $result = []; for( $i=0; $i<count( $a ); $i++ ) { for( $j=0; $j<count( $all ); $j++ ) { $result[] = $all[ 3*(($i+$j*2)%3>0)-(($i+$j*2)%3) ][ $i ]; } } print_r($result);
Output for 8.0.1 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
Array ( [0] => a1 [1] => b1 [2] => c1 [3] => c2 [4] => a2 [5] => b2 [6] => b3 [7] => c3 [8] => a3 [9] => a4 [10] => b4 [11] => c4 )
preferences:
85.13 ms | 1126 KiB | 4 Q