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<?php $titles = [ 10 => 'Mr', '20' => 'Mrs', ]; echo $titles['10 '], "\n"; echo $titles[20], "\n";
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
Warning: Undefined array key "10 " in /in/k3Ct1 on line 7 Mrs
Output for 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.31, 7.4.0 - 7.4.33
Notice: Undefined index: 10 in /in/k3Ct1 on line 7 Mrs
Output for 7.3.32 - 7.3.33
Mrs

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228.48 ms | 401 KiB | 283 Q