基本概念The stack mechanism is known as Last In First Out (LIOF), because the last item inserted is the first one removed. Let 𝒏 be the number of elements in the stackThe space used is 𝑶(𝒏)Each operation runs in time 𝑶(𝟏)算法应用检查回文字符串Checking for palindromes匹配括号Parentheses Matching
