#include <iostream>
#include <vector>
using namespace std;
class Node{
public:
    Node* left;
    Node* right;
    virtual void PrintInOrder(){}
    void getInfo();
    virtual double evaluate(){return 0;}
};
class operation : public Node{
public:
    char info;
    void PrintInOrder(){
    if(!this)return;
    if(left)left->PrintInOrder();
    cout<<info;
    if(right)right->PrintInOrder();

    }
    double evaluate(){
    if(info=='+'){
        return left->evaluate()+right->evaluate();
    }

    if(info=='*'){
        return left->evaluate()*right->evaluate();
    }

    if(info=='/'){
        return left->evaluate()/right->evaluate();
    }

    if(info=='-'){
        return left->evaluate()-right->evaluate();
    }

    }

//    void getInfo(){return info;}
};

class number : public Node{
public:


    double info;

    void PrintInOrder(){
    if(!this)return;
    if(left)left->PrintInOrder();
    cout<<info;
    if(right)right->PrintInOrder();
    }
    double evaluate(){
    return info;
    }
//
//    void getInfo(){return info;}
};
void seekCertainOperator(char Op,vector<Node*>&Input){


    for(int i=0;i<Input.size();i++){
        if(((operation*)Input[i])->info==Op){
                Input[i]->left=Input[i-1];
                Input[i]->right=Input[i+1];
                Input.erase(Input.begin()+i-1);
                Input.erase(Input.begin()+i);
        }
    }
}
void allOperator(vector<Node*>&Input){
    seekCertainOperator('*',Input);
    seekCertainOperator('/',Input);
    seekCertainOperator('+',Input);
    seekCertainOperator('-',Input);
}
vector<Node*> Transform(string In){
    vector <Node*> Temp;
    for(int i=0;i<In.size();i++){
        if(In[i]>='0'&&In[i]<='9'){
            Node *Temp1= new number();
            ((number*)Temp1)->info=In[i]-'0';
            Temp1->left=NULL;
            Temp1->right=NULL;
            Temp.push_back(Temp1);
        }else{
            Node*Temp1=new operation;
            ((operation*)Temp1)->info=In[i];
            Temp1->left=NULL;
            Temp1->right=NULL;
            Temp.push_back(Temp1);
        }

    }
    return Temp;
}
int main()
{
    vector<Node*> Equation;
    string Input="6+5*9/8-6/4*7+2";
    Equation=Transform(Input);
    allOperator(Equation);
    Equation[0]->PrintInOrder();
    cout<<" = "<<Equation[0]->evaluate();
    return 0;
}