#include <iostream>
#include <string>

using namespace std;

template<class T>
struct Node
{
    T data;
    Node* next=nullptr;
};

template<class T>
class Stack
{
private:
    Node<T>* first=nullptr;
public:
    void add_element(T data)
    {
        if(first==nullptr)
        {
            Node<T>* a = new Node<T>;
            a->data=data;
            first=a;
        }
        else
        {
            Node<T>* current=first;
            while(current->next!=nullptr)
            {
                current=current->next;
            }
            Node<T>* a = new Node<T>;
            a->data=data;
            current->next=a;
        }
    }
    T peak()
    {
        Node<T>* current=first;
        while(current->next!=nullptr)
        {
            current=current->next;
        }
        return current->data;
    }
    void pop()
    {
        Node<T>* current=first;
        if(current->next==nullptr)
        {
            delete current;
            first=nullptr;
        }
        else
        {
            while(current->next->next!=nullptr)
            {
                current=current->next;
            }
            delete current->next;
            current->next=nullptr;
        }
    }
    void print()
    {
        Node<T>* current=first;
        while(current!=nullptr)
        {
            cout<<current->data;
            current=current->next;
        }
    }
    bool empt()
    {
        return first==nullptr;
    }

};

int main()
{
    Stack<char> s;

    string sentence;
    cout<<"Enter equazion: ";
    cin>>sentence;
    //sentence="1+(3+2-[2+3]*4-{<3+1>*(4-2)})";
    for(int i=0;i<sentence.size();i++)
    {
       if(sentence[i]=='('||sentence[i]=='{'||sentence[i]=='['||sentence[i]=='<')
            {
                s.add_element(sentence[i]);
            }
        if(sentence[i]==')'||sentence[i]=='}'||sentence[i]==']'||sentence[i]=='>')
        {
            if(sentence[i]==')'&&s.peak()=='(')
            {
                s.pop();
            }
            else if(sentence[i]=='}'&&s.peak()=='{')
            {
                s.pop();
            }
            else if(sentence[i]==']'&&s.peak()=='[')
            {
                s.pop();
            }
            else if(sentence[i]=='>'&&s.peak()=='<')
            {
                s.pop();
            }
            else
            {
                cout<<"Error"<<endl;
                break;
            }
        }
    }
    if(s.empt()==1)
    {
        cout<<"Correct"<<endl;
        return s.empt()==1;
    }
    else
    {
        cout<<"Sorry"<<endl;
        return s.empt()==1;
    }
}