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Output for 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.31, 8.2.0 - 8.2.27, 8.3.0 - 8.3.18, 8.4.1 - 8.4.5
Array ( [0] => Array ( [0] => K+ [1] => K [2] => + ) [1] => Array ( [0] => Cr7+ [1] => Cr [2] => 7+ ) [2] => Array ( [0] => O2- [1] => O [2] => 2- ) )

preferences:
140.4 ms | 413 KiB | 5 Q