結果
| 問題 |
No.1002 Twotone
|
| コンテスト | |
| ユーザー |
mkawa2
|
| 提出日時 | 2025-05-16 00:27:24 |
| 言語 | PyPy3 (7.3.15) |
| 結果 |
AC
|
| 実行時間 | 3,634 ms / 5,000 ms |
| コード長 | 3,251 bytes |
| コンパイル時間 | 421 ms |
| コンパイル使用メモリ | 82,232 KB |
| 実行使用メモリ | 251,720 KB |
| 最終ジャッジ日時 | 2025-05-16 00:28:23 |
| 合計ジャッジ時間 | 57,137 ms |
|
ジャッジサーバーID (参考情報) |
judge2 / judge3 |
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| ファイルパターン | 結果 |
|---|---|
| sample | AC * 2 |
| other | AC * 33 |
ソースコード
import sys
sys.setrecursionlimit(200005)
# sys.set_int_max_str_digits(200005)
int1 = lambda x: int(x)-1
pDB = lambda *x: print(*x, end="\n", file=sys.stderr)
p2D = lambda x: print(*x, sep="\n", end="\n\n", file=sys.stderr)
def II(): return int(sys.stdin.readline())
def LI(): return list(map(int, sys.stdin.readline().split()))
def LLI(rows_number): return [LI() for _ in range(rows_number)]
def LI1(): return list(map(int1, sys.stdin.readline().split()))
def LLI1(rows_number): return [LI1() for _ in range(rows_number)]
def SI(): return sys.stdin.readline().rstrip()
# dij = [(0, 1), (-1, 0), (0, -1), (1, 0)]
dij = [(0, 1), (-1, 0), (0, -1), (1, 0), (1, 1), (1, -1), (-1, 1), (-1, -1)]
# inf = -1-(-1 << 31)
inf = -1-(-1 << 62)
# md = 10**9+7
md = 998244353
# 重心を再帰的に求める
def centroid_finder(to, root=0):
centroids = []
pre_cent = []
subtree_size = []
n = len(to)
roots = [(root, -1, 1)]
size = [1]*n
is_removed = [0]*n
parent = [-1]*n
while roots:
root, pc, update = roots.pop()
parent[root] = -1
if update:
stack = [root]
dfs_order = []
while stack:
u = stack.pop()
size[u] = 1
dfs_order.append(u)
for v,_ in to[u]:
if v == parent[u] or is_removed[v]: continue
parent[v] = u
stack.append(v)
for u in dfs_order[::-1]:
if u == root: break
size[parent[u]] += size[u]
c = root
while 1:
mx, u = size[root]//2, -1
for v,_ in to[c]:
if v == parent[c] or is_removed[v]: continue
if size[v] > mx: mx, u = size[v], v
if u == -1: break
c = u
centroids.append(c)
pre_cent.append(pc)
subtree_size.append(size[root])
is_removed[c] = 1
for v,_ in to[c]:
if is_removed[v]: continue
roots.append((v, c, v == parent[c]))
return centroids
from collections import Counter
n,k=LI()
to=[[] for _ in range(n)]
for _ in range(n-1):
u,v,c=LI1()
to[u].append((v,c))
to[v].append((u,c))
def dfs(v,c,r):
cr,sr=Counter(),Counter()
cr[-1,c]=1
sr[-1]=1
if fin[v]:return cr,sr
st=[(v,r,-1,c)]
while st:
u,p,x,y=st.pop()
for v,c in to[u]:
if v==p:continue
if x!=-1 and x!=c and y!=c:continue
nx,ny=x,y
if nx==-1 and ny!=c:
nx=c
if nx>ny:nx,ny=ny,nx
cr[nx,ny]+=1
if nx==-1:
sr[-1]+=1
else:
sr[nx]+=1
sr[ny]+=1
if fin[v]:continue
st.append((v,u,nx,ny))
return cr,sr
rr=centroid_finder(to)
# print(rr)
fin=[0]*n
ans=0
for r in rr:
fin[r]=1
cnt,sub=Counter(),Counter()
for v,c in to[r]:
cr,sr=dfs(v,c,r)
for x,y in cr:
if x==-1:
ans+=cr[x,y]*(sub[-1]-cnt[-1,y]+sub[y])
else:
ans+=cr[x,y]*(cnt[-1,x]+cnt[-1,y]+cnt[x,y])
# print(ans,v,cr,sr,cnt,sub)
cnt+=cr
sub+=sr
print(ans)
mkawa2