Searching for a particular element in a stack

Question

I am interested in porting this Python code to C++. As part of the port, I am using std::stack from the header. How can I determine w

Answer 1

If you need to search in the stack frequently, consider using a set alongside. Always keep the set updated too: if any element is popped from stack, erase it from the set , and on any push operation onto the stack, insert into the set too.

stack st; 
set s;  


//push 
st.push(2);s.insert(2);

//pop
s.erase(st.top()); st.pop();

//find (what your main objective was)
bool ispresent = s.find(2)!=s.end() ; // on failure the iterator = s.end()