VJ_ACboy needs your help again_stack_queue

//
// #include<bits/stdc++.h>
#include<iostream>
#include<stack>
#include<queue>
#include<string>
using namespace std;

int main()
{
    string s,op;
    int t,n,x;

    cin>>t;
    while( t-- )
    {
        cin>>n>>s;
        if( s=="FIFO" )
        {
            queue<int> q; 
            while( n-- )
            {
                cin>>op;
                if( op=="IN" ) { cin>>x; q.push( x ); }
                else if( op=="OUT" )
                {
                    if( q.empty() ) cout<<"None"<<endl;
                    else { cout<<q.front()<<endl; q.pop(); }
                }
            }
        }
        else if( s=="FILO" )
        {
            stack<int> sk;
            while( n-- )
            {
                cin>>op;
                if( op=="IN" ) { cin>>x; sk.push( x ); }
                else if( op=="OUT" )
                {
                    if( sk.empty() ) cout<<"None"<<endl;
                    else { cout<<sk.top()<<endl; sk.pop(); }
                }
            }
        }           // FILO
    }               // t
    return 0;
}