我已经通过这道算法题！ https://www.nowcoder.com/questionTerminal/7b18aa6b7cc14f8eaae6b8acdebf890b

有点复杂，但方便新手理解 #include<iostream> #include<stack> #include<cstdio> #include<cstring> #include<cctype> using namespace std; stack<int> mystack; void operate(string str){ if(str[0]=='A'){ if(mystack.empty()){ cout<<'E'<<endl; } else{ cout<<mystack.to...