#include <bits/stdc++.h>
using namespace std;
#define int long long
typedef pair<int,int> pi;
#define f first
#define s second
#define FAST ios_base::sync_with_stdio(0); cin.tie(0);
#define all(x) x.begin(),x.end()
const int maxn = 410;
const int mod = 1e9+7;
typedef long double ld;
const ld INF = 10005;
int n, K;
vector <int> adjlist[maxn];
int best[maxn][21];
int dp[1 << 20];
int co = 0;
void dfs(int x, int d, int p) {
if (d == K - 1) {
best[co][K-1] = co+1;
co++;
return;
}
int pref = co;
for (auto i: adjlist[x]) if (i != p) {
dfs(i, d + 1, x);
}
int post = co;
for (int i = pref; i < post; i++) {
best[i][d] = post;
}
}
int32_t main() {
FAST
cin >> n >> K;
for (int i =0;i<n-1;i++) {
int a,b; cin >> a >> b;
adjlist[a].push_back(b);
adjlist[b].push_back(a);
}
if (n - 1 < K * (K+1)) {
cout << "DA";
return 0;
}
dfs(1, -1, -1); //node 1 is depth -1 so that its children are depth 0
for (int bm = 1; bm < (1 << K); bm++) {
int res = 0;
for (int d = 0; d < K; d++) {
if (~bm & (1 << d)) continue;
res = max(res, best[dp[bm ^ (1 << d)]][d]);
}
dp[bm] = res;
if (res == co) {
cout << "DA";
return 0;
}
}
cout << "NE";
}
