#include "garden.h"
#include "gardenlib.h"
#include <iostream>
#include <vector>
#include <algorithm>
#include <set>
#include <map>
#include <climits>
#include <cstring>
using namespace std;
using ll = long long;
using ull = unsigned long long;
using vi = vector<int>;
using ii = pair<int,int>;
using vii = vector<pair<int,int>>;
using vb = vector<bool>;
template<typename T>
using Graph = vector<vector<T>>;
struct Node
{
int v, i;
bool operator< (const Node& a) const
{
return i < a.i;
}
};
bool path(int u, int v, int k, const Graph<Node>& graph)
{
int t = -1;
while(k--)
{
if(graph[u][0].i == t && graph[u].size() > 1)
{
t = graph[u][1].i;
u = graph[u][1].v;
} else
{
t = graph[u][0].i;
u = graph[u][0].v;
}
}
return u == v;
}
// self loops ?
void count_routes(int N, int M, int P, int R[][2], int Q, int G[])
{
if(Q != 1) abort();
Graph<Node> graph(N);
for(int i = 0; i < M; ++i)
{
graph[R[i][0]].push_back(Node { R[i][1], i });
graph[R[i][1]].push_back(Node { R[i][0], i });
}
for(auto x: graph) sort(x.begin(), x.end());
int r = 0;
for(int i = 0; i < N; ++i)
{
if(path(i, P, G[0], graph)) ++r;
}
answer(r);
}
