STL_queue

#include<iostream>
#include<algorithm>
#include<queue>
using namespace std;

void main(){
  queue<int>s;
  s.push(1);
  s.push(2);
  s.push(3);
  cout<<"size::"<<s.size()<<endl;
  cout<<"front::"<<s.front()<<endl;
  cout<<"back::"<<s.back()<<endl;
  cout<<endl;

  s.pop();
  cout<<"size::"<<s.size()<<endl;
  cout<<"front::"<<s.front()<<endl;
  cout<<"back::"<<s.back()<<endl;
  cout<<endl;
  if(s.empty()){
        cout << "Is empty" << endl;
    }else{
        cout << "Is not empty" << endl;
    }
    
    return ;

}