Try all ways to partition and check if each letter stays in one part.
With length , there are ways to place partition boundaries. Checking each is expensive.
Can you find where each partition must end?
##### ###### ##### ### # # ### # # ###### ## ## ## ## ## ## ## # # # # # ## ##### #### ##### # # # # # # # #### ## # ## ## ## ## # # # # # ## ## # ###### ## ### # ### # ######
$ curl repovive.com/roadmaps/pattern-22/greedy/partition-labels-why-naive-fails
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