Converting 4 × (2 × 4³ + 5) to postfix, one token at a time. Watch when a token is pushed onto the operator stack versus when it's popped into the output queue — the rules that decide are precedence, associativity, and brackets.
Top of stack is highlighted. A ( blocks any operator below it from being popped.
Reading left to right, this is the postfix expression as it's built.
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