3v4l.org

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<?php $str = "1,5"; $base = array('1'=>'Bread','5'=>'Butter'); $flipped = array_flip( explode(',', $str)); print_r( $flipped); print_r( array_merge( $flipped, $base)); $intersection = array_intersect_key( array_merge( $flipped, $base), $flipped); print_r( $intersection); $replacements = array_values( $intersection); print_r( $replacements);

preferences:
39.85 ms | 402 KiB | 5 Q