#include<bits/stdc++.h> //:3
using namespace std;
typedef long long ll;
#define all(a) (a).begin(), (a).end()
#define ff first
#define ss second
#define pb push_back
#define mp make_pair
#define pi pair<int, int>
#define sz(x) (int)((x).size())
#include "coins.h"
const int dx[] = {0, 1, 0, -1};
const int dy[] = {1, 0, -1, 0};
const ll inf = 2e9;
const ll mod = 1e9 + 7;
const int N = 2e3 + 11;
const ll INF64 = 3e18 + 1;
const double eps = 1e-14;
const double PI = acos(-1);
vector<int> coin_flips(vector<int> b, int c){
int x = 0;
for(int i = 0; i < 64; i++){
if(b[i]) x ^= i;
}
vector<int>X;
X.push_back(x ^ c);
return X;
}
int find_coin(vector<int> b){
int x = 0;
for(int i = 0; i < 64; i++){
if(b[i]) x ^= i;
}
return x;
}
