Tag:Question surface

  • Print binary tree from top to bottom

    Time:2020-11-5

    Python is short and sharp, and golang is simple and efficient Question surface Each node of the binary tree is printed from top to bottom, and the nodes of the same layer are printed from left to right.Given binary tree[3,9,20,null,null,15,7], 3 / \ 9 20 / \ 15 7 return [3,9,20,15,7] python Queue in and […]

  • Inverse Polish expression evaluation Python vs golang

    Time:2020-10-28

    Stack has great advantages in some matching scenarios and is very computer-friendly Question surface Calculate the value of inverse Polish (suffix expression), integer division only retains the integer partOperator contains only”+”,”-“,”*”and”/”The operands may be integers or other expressions [“20”, “10”, “+”, “30”, “*”] -> ((20 + 10) * 30) -> 900 [“40”, “130”, “50”, “/”, […]