Uva 10940 Throwing cards Josephs problem

uva10940.cpp

#include<vector>
#include<algorithm>
#include<cstdio>
#include<cstring>
#include<cmath>
#include <iostream>
#include <map>
#include <queue>
#include <set>
#include <string>
#include<limits>
using namespace std;

#define fi(i,a,b) for(int i=(int)a;i<=(int)b;i++)
#define fd(i,a,b) for(int i=(int)a;i>=(int)b;i--)
#define rep(i,n) fi(i,0,n-1)
//stl
#define sz(a) int((a).size())
#define pb push_back
#define all(c) ((c).begin(),(c).end())
#define tr(c,i) for(typeof((c).begin()) i = (c).begin(); i != (c).end(); i++)
#define present(c,x) ((c).find(x) != (c).end())
#define cpresent(c,x) (find(all(c),x) != (c).end())

typedef long long ll;
typedef vector<int> vi;
typedef pair<int, int> ii;
typedef vector<ii>    vii;
typedef vector<vi> vvi;
typedef vector<vii> vvii;



int main()
{
    int c[50001],d[50001];
    c[1]=d[1]=1;
    c[2]=2;d[2]=1;
    fi(i,3,50000)
    {
        if(i%2)
        {
            c[i]=d[i/2]*2;
            d[i]=2*c[i/2+1]-1;
        }
        else
        {
            c[i]=2*c[i/2];
            d[i]=d[i/2]*2-1;
        }
    }
    int n;
    while(cin>>n && n)
        cout<<c[n]<<endl;
    return 0;
}