-
Notifications
You must be signed in to change notification settings - Fork 1
/
P3915.cc
49 lines (45 loc) · 1 KB
/
P3915.cc
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
#include <cstdio>
#include <cstdlib>
#include <vector>
using std::vector;
#define maxn 100000
vector<int> tree[maxn];
int f[maxn];
int k, cnt;
void dfs(int t, int p) {
f[t] = 1;
for (int i = 0; i < tree[t].size(); i++) {
if (tree[t][i] == p) continue;
dfs(tree[t][i], t);
f[t] += f[tree[t][i]];
}
if (f[t] == k) {
cnt++;
f[t] = 0;
}
}
int main() {
int t, n, a, b;
scanf("%d", &t);
while (t) {
t--;
scanf("%d %d", &n, &k);
if (n % k) {
printf("NO\n");
for (int i = 0; i < n - 1; i++) scanf("%d %d", &a, &b);
continue;
}
for (int i = 0; i < n; i++) tree[i].clear();
for (int i = 0; i < n - 1; i++) {
scanf("%d %d", &a, &b);
a--;b--;
tree[a].push_back(b);
tree[b].push_back(a);
}
cnt = 0;
dfs(0, 0);
if (cnt == n/k) printf("YES\n");
else printf("NO\n");
}
return 0;
}