#include <bits/stdc++.h>
using namespace std;
const double pi = acos(-1.0);
const double eps = 1e-11;
const int inf = 0x7FFFFFFF;
template <class T>
inline void checkmin(T &a, T b) {
  if (b < a) a = b;
}
template <class T>
inline void checkmax(T &a, T b) {
  if (b > a) a = b;
}
template <class T>
inline T sqr(T x) {
  return x * x;
}
template <class T>
void show(T a, int n) {
  for (int i = 0; i < n; ++i) cout << a[i] << ' ';
  cout << endl;
}
template <class T>
void show(T a, int r, int l) {
  for (int i = 0; i < r; ++i) show(a[i], l);
  cout << endl;
}
const int N = 150005;
int to[N], nxt[N];
int vis[N], head[N];
int n, k, ec;
long long ans;
int cc[50001][501];
void add(int u, int v) {
  to[ec] = v;
  nxt[ec] = head[u];
  head[u] = ec++;
}
void dfs(int now) {
  vis[now] = true;
  int v, e, *src = cc[now], *dst;
  src[0]++;
  for (e = head[now]; e != -1; e = nxt[e]) {
    v = to[e];
    if (!vis[v]) {
      dfs(v);
      dst = cc[v];
      for (int i = 0; i <= k - 1; i++)
        ans += ((long long)src[i]) * dst[k - 1 - i];
      for (int i = 0; i <= k - 1; i++) src[i + 1] += dst[i];
    }
  }
}
int main() {
  while (cin >> n >> k) {
    memset(head, -1, sizeof(head));
    for (int i = 1; i < n; i++) {
      int a, b;
      cin >> a >> b;
      add(a, b);
      add(b, a);
    }
    dfs(1);
    cout << ans << endl;
  }
  return 0;
}
