#include <bits/stdc++.h>
#include <chrono>
#include <random>
#include <unordered_map>
#include <unordered_set>
#define ll long long
#define vi vector<ll>
#define vii vector<vi>
#define pl pair<ll, ll>
#define all(X) X.begin(),X.end()
#define vp vector<pl>
#define mi map<ll,ll>
#define ld long double
#define vc vector<char>
#define vcc vector<vc>
#define mc map<char,int>
#define sortx(X) sort(X.begin(),X.end());
#define allr(X) X.rbegin(),X.rend()
#define ln '\n'
#define YES {cout << "YES\n"; return;}
#define NO {cout << "NO\n"; return;}
#define MUN {cout << "-1\n"; return;}
using namespace std;
const int MODE = 998244353;
const int MXN = 410;
int dpt[MXN] = {0};
void req(vii &adj, vector<set<ll>> &ST, ll n, ll p, ll lvl, ll k) {
dpt[n] = lvl;
if (lvl >= k) {
ST[n].insert(n);
return;
}
ll cnt = 0;
for (auto neg : adj[n]) if (neg != p) {
req(adj, ST, neg, n, lvl+1, k);
ST[n].insert(all(ST[neg]));
}
}
void solve(ll tc) {
ll n, k;
cin >> n >> k;
vii adj(n + 1);
for (int i = 0; i < n-1; i++)
{
ll u, v; cin >> u >> v;
adj[u].push_back(v);
adj[v].push_back(u);
}
if (k * k >= n) {
cout << "DA\n";
return;
}
vector<set<ll>> ST(n + 1);
req(adj, ST, 1, 0, 0, k);
vector<set<ll>> st;
for (int i = 1; i <= n; i++)
{
if (dpt[i] == 1 && !ST[i].empty()) st.push_back(ST[i]);
}
for (int lvl = 2; lvl <= k; lvl++)
{
vector<set<ll>> st2(all(st));
for (int i = 1; i <= n; i++)
{
if (dpt[i] != lvl || ST[i].empty()) continue;
for (auto &s : st) {
if (s.count(*ST[i].begin())) continue;
set<ll> tmp(all(s));
tmp.insert(all(ST[i]));
st2.push_back(tmp);
}
}
swap(st, st2);
st.erase(unique(st.begin(), st.end()), st.end());
}
for (auto &s : st) {
if (s.size() == ST[1].size()) {
cout << "DA\n";
return;
}
}
cout << "NE\n";
}
int32_t main()
{
ios_base::sync_with_stdio(false), cin.tie(nullptr), cout.tie(nullptr);
int size = 1;
// freopen("disrupt.in", "r", stdin );
// freopen("disrupt.out", "w", stdout);
// cin >> size;
for (int tc = 1; tc <= size; tc++){
solve(tc);
// if (tc != size) cout << '\n';
}
}
