100daysofcode/Day61.cpp at main · NamanJain795/100daysofcode · GitHub

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class Solution {
public:
    int evalRPN(vector<string>& tokens) {
        stack<int> st;
        for(int i=0;i<tokens.size();i++){
            if(tokens[i] != "+"  && tokens[i] != "-" && tokens[i] != "/" && tokens[i] != "*"){
                st.push(stoi(tokens[i]));
            }
            else{
                int b = st.top();
                st.pop();
                int a = st.top();
                st.pop();
                if(tokens[i] == "+"){
                    st.push(a+b);
                }
                else if(tokens[i] == "-"){
                    st.push(a-b);
                }
                else if(tokens[i] == "*"){
                    st.push(a*b);
                }
                else if(tokens[i] == "/"){
                    st.push(a/b);
                }
            }
        }
        return st.top();
    }
};