UVA SOLUTION:10935 - Throwing cards away I

#include<bits/stdc++.h>
#define READ freopen("in.txt","r",stdin);
#define WRITE freopen ("out.txt","w",stdout);
using namespace std;

int main()
{
   // READ
   // WRITE
    queue<int >Q;
    queue<int>r;
    int n;
    while(cin>>n)
    {
        if(n==0) break;
        if(n==1)
        {
           cout<<"Discarded cards:"<<endl;
           cout<<"Remaining card: 1"<<endl;
            continue;
        }
        while(!Q.empty()) Q.pop();
        while(!r.empty()) r.pop();
        for(int i=1; i<=n; i++) r.push(i);
        while(r.size()>1)
        {
            int u=r.front();
            Q.push(u) ;
            r.pop();
            int x=r.front();
            r.pop();
            r.push(x);

        }
        int c=0;
        cout<<"Discarded cards: ";
        while(!Q.empty())
        {
            cout<<Q.front();
            c++;
            if(c<n-1) cout<<", ";
            Q.pop();
        }
        cout<<endl;
        cout<<"Remaining card: "<<r.front()<<endl;

    }





    return 0;
}