Method dequeue

CPP/QUEUE/QueueUsingStack.cpp:13–27

        
    }
    int dequeue(){
        while(!s1.empty()){
            s2.push(s1.top());
            s1.pop();
        }
        int ans=s2.top();
        s2.pop();
        while(!s2.empty()){
            s1.push(s2.top());
            s2.pop();
            
        }
        return ans;
        
    }
    
    
};