#include <stdio.h>
#include <stdlib.h>
#include <iostream>
#include <iomanip>
#include <cassert>
#include <vector>
#include <string.h>
#include <string>
#include <map>
#include <stack>
#include <queue>
#include <deque>
#include <set>
#include <math.h>
#include <algorithm>
#include <numeric>
#include <random>

//#include <atcoder/convolution>
//#include <atcoder/math>
//#include <atcoder/maxflow>
//#include <atcoder/mincostflow>
//#include <atcoder/modint>
//#include <atcoder/scc>
//#include <atcoder/string>
//#include <atcoder/twosat>
//using namespace atcoder;

using namespace std;


// マクロ&定数&関数 ================================================
typedef int Int;
typedef int INt;
typedef unsigned int uint;
typedef long long ll;
typedef long double ld;

typedef pair<ll, ll> pll;
typedef pair<int, int> pint;

typedef vector<int> vint;
typedef vector<ll> vll;
typedef vector<double> vdouble;
typedef vector<bool> vbool;
typedef vector<string> vstring;

typedef vector<pair<int, int>> vpint;
typedef vector<pair<ll, ll>> vpll;
typedef vector<pair<double, double>> vpdouble;

typedef vector<vector<int>> vvint;
typedef vector<vector<ll>> vvll;
typedef vector<vpint> vvpint;
typedef vector<vpll> vvpll;
typedef vector<vector<double>> vvdouble;
typedef vector<vector<string>> vvstring;
typedef vector<vector<bool>> vvbool;

typedef vector<vector<vector<ll>>> vvvll;
typedef vector<vector<vector<pll>>> vvvpll;
typedef vector<vector<vector<bool>>> vvvbool;
typedef vector<vector<vector<double>>> vvvdouble;
typedef vector<vector<vector<vector<double>>>> vvvvdouble;

const ll LLINF = 1e18 + 1;
const int DX[9] = { 0,  0, 1, -1, 1,  1, -1, -1, 0 }; // 4;４近傍
const int DY[9] = { 1, -1, 0,  0, 1, -1,  1, -1, 0 }; // 8:８近傍 9:(0,0)を含む
const double PI = 3.14159265358979323846264338327950288;
const double EPS = 1e-7;

//VVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVV

const ll MOD = 1000000007; //10^9 + 7

//VVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVV


template<class T>bool chmax(T &a, const T &b) { if (a < b) { a = b; return 1; } else return false; }
template<class T>bool chmin(T &a, const T &b) { if (b < a) { a = b; return 1; } else return false; }


//---------------------------------------------------------------
//  オーバーフローチェック
//---------------------------------------------------------------
bool is_overflow(ll a, ll b) {
    ll M = numeric_limits<ll>::max();
    return (a >= M / b);
}



//---------------------------------------------------------------
// XORの階乗 0^1^...^N (O(1))
//---------------------------------------------------------------
ll xor_fac(ll N)
{
    if (N == 0) return 0;

    ll n_pair = (N - 1) / 2;
    ll n_one = n_pair + 1;

    if (n_pair * 2 + 1 == N) {
        return n_one % 2;
    }
    else {
        return (n_one % 2) ^ N;
    }
}




int main() {

    //////==================================
    cin.tie(nullptr);
    ios_base::sync_with_stdio(false);
    cout << fixed << setprecision(25);
    //////==================================


    /*
    　　　～思いついたことはとりあえず絶対メモする！！～


    　　　　　～オーバーフローに注意！！！～
    */


    ll N;
    cin >> N;

    ll ans = xor_fac(N);

    cout << (ans != 0 ? "O" : "X") << endl;
    




}