#include <iostream>
#include <cstdlib>
#include <algorithm>
#include <cmath>
#include <vector>
#include <set>
#include <map>
#include <unordered_set>
#include <unordered_map>
#include <cstring>
using namespace std;
using ll = long long;
using ld = long double;
using uint = unsigned int;
using ull = unsigned long long;
#include "grader.h"
#include "memory.h"
#define pb push_back
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define rall(x) (x).rbegin(),(x).rend()
#define fi first
#define se second
#ifdef LOCAL
#include </home/linux/debug.h>
#define dbg(...) cout << "LINE(" << __LINE__ << ") -> [" << #__VA_ARGS__ << "]: [", _print(__VA_ARGS__)
#else
#define dbg(...)
#endif
void play()
{
int where[100],p = -1;
memset(where,-1,sizeof(where));
for(int i = 1;i<=50;i++)
{
int c = (int)(faceup(i)-'A');
if(p != -1)
p = -1;
else
p = c;
if(where[c]!=-1)
{
if(p == -1)
faceup(i);
faceup(where[c]);
p = -1;
}
else
where[c] = i;
}
}
