#define _CRT_SECURE_NO_WARNINGS
#include <string>
#include <vector>
#include <algorithm>
#include <numeric>
#include <set>
#include <map>
#include <queue>
#include <iostream>
#include <sstream>
#include <cstdio>
#include <cmath>
#include <ctime>
#include <cstring>
#include <cctype>
#include <cassert>
#include <limits>
#include <functional>
#include <unordered_map>
#define rep(i,n) for(int (i)=0;(i)<(int)(n);++(i))
#define rer(i,l,u) for(int (i)=(int)(l);(i)<=(int)(u);++(i))
#define reu(i,l,u) for(int (i)=(int)(l);(i)<(int)(u);++(i))
#if defined(_MSC_VER) || __cplusplus > 199711L
#define aut(r,v) auto r = (v)
#else
#define aut(r,v) typeof(v) r = (v)
#endif
#define each(it,o) for(aut(it, (o).begin()); it != (o).end(); ++ it)
#define all(o) (o).begin(), (o).end()
#define pb(x) push_back(x)
#define mp(x,y) make_pair((x),(y))
#define mset(m,v) memset(m,v,sizeof(m))
#define INF 0x3f3f3f3f
#define INFL 0x3f3f3f3f3f3f3f3fLL
using namespace std;
typedef vector<int> vi; typedef pair<int,int> pii; typedef vector<pair<int,int> > vpii;
typedef long long ll; typedef vector<long long> vl; typedef pair<long long,long long> pll; typedef vector<pair<long long,long long> > vpll;
typedef vector<string> vs; typedef long double ld;
template<typename T, typename U> inline void amin(T &x, U y) { if(y < x) x = y; }
template<typename T, typename U> inline void amax(T &x, U y) { if(x < y) x = y; }

int main() {
	int N, M, K;
	scanf("%d%d%d", &N, &M, &K);
	vector<vi> wf(N, vi(N, INF));
	rep(i, N) wf[i][i] = 0;
	rep(i, M) {
		int U, V;
		scanf("%d%d", &U, &V), -- U, -- V;
		wf[U][V] = wf[V][U] = 1;
	}
	rep(k, N) rep(i, N) rep(j, N)
		amin(wf[i][j], wf[i][k] + wf[k][j]);
	vi vertices;
	ll ans = 0;
	for(int v = N-1; v > 0; -- v) {
		vertices.push_back(v);
		int X = vertices.size();
		vector<int> dp((1 << X) * X, INF);
		rep(ix, vertices.size()) {
			int i = vertices[ix];
			dp[(1 << ix) * X + ix] = wf[0][i];
		}
		rep(i, 1 << X) rep(jx, X) {
			int x = dp[i * X + jx];
			if(x == INF) continue;
			int j = vertices[jx];
			rep(kx, X) if(~i >> kx & 1) {
				int k = vertices[kx];
				amin(dp[(i | 1 << kx) * X + kx], x + wf[j][k]);
			}
		}
		int t = INF;
		rep(j, X)
			amin(t, dp[((1 << X)-1) * X + j]);
//		cerr << v << ": " << t << endl;
		if(t <= K)
			ans += (1LL << v) - 1;
		else
			vertices.pop_back();
	}
	cout << ans << endl;
	return 0;
}