Process operators left to right in order.
This ignores operator precedence. 3+2*2 would incorrectly compute (3+2)*2 = 10 instead of 3+(2*2) = 7.
You need to handle * and / immediately while deferring + and - for later.
##### ###### ##### ### # # ### # # ###### ## ## ## ## ## ## ## # # # # # ## ##### #### ##### # # # # # # # #### ## # ## ## ## ## # # # # # ## ## # ###### ## ### # ### # ######
$ curl repovive.com/roadmaps/pattern-22/stack-patterns/basic-calculator-ii-why-naive-fails
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