#include <bits/stdc++.h>
#define pb push_back
#define ff first
#define ss second
#define chmin(a,b) a=min(a,b)
#define chmax(a,b) a=max(a,b)
using namespace std;
using VI = vector <int>;
using PII = pair <int, int>;
const int N = 401;
const int K = 21;
const int M = 1<<20;
VI paths[N];
int dp[M], reach[K][N];
int n, m, k, leaf;
string yes = "DA";
string no = "NE";
PII dfs(int pos, int lvl = -1, int par = -1) {
int l = n, r = -1;
if (lvl == k-1) {
l = r = leaf++;
chmax(reach[lvl][l], r);
// cout << pos << "," << lvl << ": " << l << "," << r << '\n';
return {l, r};
}
for (auto el : paths[pos]) {
if (el == par) continue;
PII tmp = dfs(el, lvl+1, pos);
chmin(l, tmp.ff);
chmax(r, tmp.ss);
}
if (l == n) chmax(reach[lvl][l], r);
// cout << pos << "," << lvl << ": " << l << "," << r << '\n';
return {l, r};
}
signed main() {
ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
// freopen("0.in", "r", stdin);
// freopen("0.out", "w", stdout);
cin >> n >> k;
for (int i = 1; i < n; i++) {
int a, b; cin >> a >> b;
paths[a].pb(b);
paths[b].pb(a);
}
if (k*k >= n) {
cout << yes << "\n";
return 0;
}
memset(reach, -1, sizeof(reach));
n = dfs(1).ss;
for (int i = 0; i < k; i++)
for (int j = 1; j <= n; j++) chmax(reach[i][j], reach[i][j-1]);
memset(dp, -1, sizeof(dp));
dp[0] = 0;
// cout << n << "\n";
for (int i = 0; i < (1<<k); i++) {
dp[i] = 0;
// cout << "------------------\n";
// cout << i << "\n";
for (int j = 0; j < k; j++) {
int prev = i ^ (1<<j);
if (prev > i) continue;
// cout << j << " " << dp[prev] << ": " << reach[j][dp[prev]]+1 << "\n";
chmax(dp[i], reach[j][dp[prev]]+1);
}
// cout << i << ": " << dp[i]-1 << '\n';
if (dp[i] > n) {
cout << yes << '\n';
return 0;
}
}
cout << no << "\n";
}
