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run code in 500+ PHP versions simultaneously
<?php $re = '/^(#\h*)((\[\d+]|\{\d+}|\(\d+\))(?:\h+(?3))*)$/m'; $str = '# [1] {1} [2] {10} [3] [3] [4] {10} {100} [1] [5] # [5] {1} [6] (10) (20) (10) {10} [7] [5] [6] {10} {100} [8] [5] (10) (30) # (10) (30) [7] {1} [8] {10} [9] [7] [8] {100} {101} [9] [5] {101} (50)'; preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0); echo implode("\n", array_map(fn($x) => $x[1] . implode(' ', array_unique(explode(' ', $x[2]))), $matches));
Output for 7.4.0 - 7.4.33, 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
# [1] {1} [2] {10} [3] [4] {100} [5] # [5] {1} [6] (10) (20) {10} [7] {100} [8] (30) # (10) (30) [7] {1} [8] {10} [9] {100} {101} [5] (50)
preferences:
83.46 ms | 1262 KiB | 4 Q