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<?php function solution($set) { $diff = array_diff(range(1, max($set)), $set); sort($diff); return !isset($diff[0]) ? max($set) + 1 : ($diff[0] < 1 ? 1 : $diff[0]); } echo solution([39, 68, 47, 2, 19, 64]).PHP_EOL; echo solution([1, 3, 6, 4, 1, 2]).PHP_EOL; echo solution([1, 2, 3]).PHP_EOL; echo solution([-1, -3]).PHP_EOL;
Output for 7.1.25 - 7.1.27, 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 - 8.1.34, 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 5 4 1
preferences:
98.98 ms | 1390 KiB | 4 Q