#include <bits/stdc++.h>
#define ff first
#define ss second
#define endl '\n'
using namespace std;
const long long INF = (long long) 1e18;
const int mod = (int) 1e9+7;
const int MAXN = (int) 3000;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
ll n, k;
vector<int> adj[MAXN];
int dep[MAXN];
int gir[MAXN];
int cik[MAXN];
int yapraksayi = 0;
bool dp[405][(1<<20)];
vector<int> q[MAXN];
void dfs(int a, int par){
if(par != -1) dep[a] = dep[par] + 1;
if(dep[a] == k){
gir[a] = yapraksayi;
cik[a] = yapraksayi;
yapraksayi++;
return;
}
gir[a] = yapraksayi;
for(int i: adj[a]){
if(i != par) dfs(i, a);
}
cik[a] = yapraksayi - 1;
}
bool do_it(){
for(int i = 2; i <= n; i++){
if(!dep[i]) continue;
dep[i]--;
q[gir[i]].push_back(i);
//cout<<gir[i]<<endl;
//cout<<dep[i]<<endl;
}
//return 0;
dp[0][0] = 1;
for(int i = 0; i < yapraksayi; i++){
for(int j = 0; j < (1<<20); j++){
if(!dp[i][j]) continue;
for(int k: q[i]){
if(((j>>dep[k]) & 1) == 0){
dp[cik[k] + 1][j | (1<<dep[k])] = 1;
//cout<<cik[k] + 1<<endl;
}
}
}
}
for(int i = 0; i < (1<<20); i++){
if(dp[yapraksayi][i]) return 1;
}
return 0;
}
int main(){
ios_base::sync_with_stdio(false);
cin.tie(nullptr);cout.tie(nullptr);
#ifdef Local
freopen("../IO/int.txt","r",stdin);
freopen("../IO/out.txt","w",stdout);
#endif
cin>>n>>k;
if(k*(k + 1) >= 2*n){
cout<<"DA"<<endl;
return 0;
}
for(int i = 0; i < n - 1; i++){
int a, b;
cin>>a>>b;
adj[a].push_back(b);
adj[b].push_back(a);
}
dep[1] = 0;
dfs(1, -1);
cout<<(do_it() ? "DA" : "NE")<<endl;
#ifdef Local
cout<<endl<<fixed<<setprecision(2)<<1000.0 * clock() / CLOCKS_PER_SEC<< " milliseconds ";
#endif
}
