import java.io.*;
import java.util.*;
public class burza {
public static int num; public static int k; public static HashMap<Integer, ArrayList<Integer>> tree;
public static int[] depth; public static int[][] interval; //Interval of leaves covered by a node
public static int count; public static HashMap<Integer, Integer> idx;
public static void main(String[] args) throws IOException {
BufferedReader scan = new BufferedReader(new InputStreamReader(System.in));
StringTokenizer l1 = new StringTokenizer(scan.readLine());
num = Integer.parseInt(l1.nextToken()); k = Integer.parseInt(l1.nextToken()); tree = new HashMap<>();
for (int i = 0;i<num;i++) tree.put(i,new ArrayList<>());
for (int i = 0;i<num-1;i++) {
StringTokenizer st = new StringTokenizer(scan.readLine());
int a = Integer.parseInt(st.nextToken())-1; int b = Integer.parseInt(st.nextToken())-1;
tree.get(a).add(b); tree.get(b).add(a);
}
if (k*k>=num) System.out.println("NE");
else System.out.println(solve());
}
public static String solve () {
idx = new HashMap<>(); count = 0;
depth = new int[num];
Arrays.fill(depth, -1); depth[0] = 0;
dfs1(0);
interval = new int[num][2];
for (int i = 0;i<num;i++) {
interval[i][0] = Integer.MAX_VALUE; interval[i][1] = Integer.MIN_VALUE;
}
count = 0;
for (int i = 0;i<num;i++) {
if (depth[i]==k) {
interval[i][0] = idx.get(i); interval[i][1] = idx.get(i);
dfs2(i,i); count++;
}
}
//System.out.println(idx);
/*for (int i = 0;i<num;i++) {
System.out.println(interval[i][0]+" "+interval[i][1]);
}*/
int[] dp = new int[1<<k];
Arrays.fill(dp, -1); dp[0] = 0;
for (int i = 1;i<1<<k;i++) {
for (int j = 0;j<k;j++) {
if ((i&(1<<j))==0) continue;
int prev = i-(1<<j);
for (int l = 0;l<num;l++) {
if (depth[l]!=j+1) continue;
if (interval[l][0]<=dp[prev]+1) {
dp[i] = Math.max(dp[i], interval[l][1]);
}
}
}
}
for (int i = 0;i<(1<<k);i++) {
if (dp[i] == count - 1) return "DA";
}
return "NE";
}
public static void dfs1 (int curr) {
for (int next : tree.get(curr)) {
if (depth[next]==-1) {
depth[next] = depth[curr]+1;
if (depth[next]==k) {
idx.put(next, count); count++;
}
dfs1(next);
}
}
}
public static void dfs2 (int curr, int child) {
for (int next : tree.get(curr)) {
if (depth[next]<depth[curr]) { //Going up the tree
if (idx.get(child)<interval[next][0]) interval[next][0] = idx.get(child);
if (idx.get(child)>interval[next][1]) interval[next][1] = idx.get(child);
dfs2(next, child);
}
}
}
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
112 ms |
23512 KB |
Output is correct |
2 |
Correct |
639 ms |
25560 KB |
Output is correct |
3 |
Incorrect |
53 ms |
22528 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
613 ms |
22824 KB |
Output is correct |
2 |
Correct |
605 ms |
23392 KB |
Output is correct |
3 |
Incorrect |
54 ms |
22304 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
619 ms |
23092 KB |
Output is correct |
2 |
Correct |
577 ms |
23524 KB |
Output is correct |
3 |
Incorrect |
59 ms |
22360 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
207 ms |
26952 KB |
Output is correct |
2 |
Incorrect |
625 ms |
22716 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
585 ms |
22896 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
600 ms |
23264 KB |
Output is correct |
2 |
Correct |
634 ms |
25716 KB |
Output is correct |
3 |
Incorrect |
54 ms |
22480 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
691 ms |
22936 KB |
Output is correct |
2 |
Correct |
617 ms |
23296 KB |
Output is correct |
3 |
Incorrect |
55 ms |
22736 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
185 ms |
23180 KB |
Output is correct |
2 |
Correct |
598 ms |
25296 KB |
Output is correct |
3 |
Incorrect |
55 ms |
24108 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
97 ms |
23484 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
272 ms |
25536 KB |
Output is correct |
2 |
Correct |
618 ms |
25188 KB |
Output is correct |
3 |
Incorrect |
54 ms |
22608 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |