Comment on K: We need to talk about groupparentComments−co_dh3yGroup is actually like inverse a mapping. Given an array A which map index to value, group A map value to index. A common idiom is: desc count each group A , which list most frequent element first
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Group is actually like inverse a mapping. Given an array A which map index to value, group A map value to index. A common idiom is: desc count each group A , which list most frequent element first