663 B | 663 chars
#include <bits/stdc++.h>
#define for1(s,n) for(int i = s; i < n; i++)
#define for1j(s,n) for(int j = s; j < n; j++)
#define foreach(k) for(auto i : k)
#define foreachj(k) for(auto j : k)
#define pb(a) push_back(a)
#define sz(a) a.size()
using namespace std;
typedef unsigned long long ull;
typedef long long ll;
typedef vector <int> iv1;
typedef vector <vector<int> > iv2;
typedef vector <ll> llv1;
typedef unsigned int uint;
typedef vector <ull> ullv1;
typedef vector <vector <ull> > ullv2;
int ar[] = {0, 1, 0, 1, 1, 1, 1};
int main() {
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int cnt;
cin >> cnt;
cout <<( ar[cnt % 7] ? "SK" : "CY");
}