結果
問題 | No.2316 Freight Train |
ユーザー |
|
提出日時 | 2023-05-26 21:44:00 |
言語 | PyPy3 (7.3.15) |
結果 |
AC
|
実行時間 | 634 ms / 2,000 ms |
コード長 | 2,215 bytes |
コンパイル時間 | 412 ms |
コンパイル使用メモリ | 81,920 KB |
実行使用メモリ | 108,032 KB |
最終ジャッジ日時 | 2024-12-25 05:58:15 |
合計ジャッジ時間 | 15,179 ms |
ジャッジサーバーID (参考情報) |
judge4 / judge1 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 3 |
other | AC * 26 |
ソースコード
import sys from collections import deque, Counter input = lambda: sys.stdin.readline().rstrip() ii = lambda: int(input()) mi = lambda: map(int, input().split()) li = lambda: list(mi()) inf = 2 ** 63 - 1 mod = 998244353 class dsu(): n=1 parent_or_size=[-1 for i in range(n)] def __init__(self,N): self.n=N self.num = N self.parent_or_size=[-1 for i in range(N)] def merge(self,a,b): assert 0<=a<self.n, "0<=a<n,a={0},n={1}".format(a,self.n) assert 0<=b<self.n, "0<=b<n,b={0},n={1}".format(b,self.n) x=self.leader(a) y=self.leader(b) if x==y: return x self.num -= 1 if (-self.parent_or_size[x]<-self.parent_or_size[y]): x,y=y,x self.parent_or_size[x]+=self.parent_or_size[y] self.parent_or_size[y]=x return x def same(self,a,b): assert 0<=a<self.n, "0<=a<n,a={0},n={1}".format(a,self.n) assert 0<=b<self.n, "0<=b<n,b={0},n={1}".format(b,self.n) return self.leader(a)==self.leader(b) def leader(self,a): assert 0<=a<self.n, "0<=a<n,a={0},n={1}".format(a,self.n) if (self.parent_or_size[a]<0): return a self.parent_or_size[a]=self.leader(self.parent_or_size[a]) return self.parent_or_size[a] def size(self,a): assert 0<=a<self.n, "0<=a<n,a={0},n={1}".format(a,self.n) return -self.parent_or_size[self.leader(a)] def groups(self): leader_buf=[0 for i in range(self.n)] group_size=[0 for i in range(self.n)] for i in range(self.n): leader_buf[i]=self.leader(i) group_size[leader_buf[i]]+=1 result=[[] for i in range(self.n)] for i in range(self.n): result[leader_buf[i]].append(i) result2=[] for i in range(self.n): if len(result[i])>0: result2.append(result[i]) return result2 def count(self): return self.num n, q = mi() p = li() U = dsu(n) for i in range(n): if p[i] == -1: continue else: U.merge(i, p[i] - 1) for _ in range(q): a, b = mi() a -= 1; b -= 1 print('Yes' if U.same(a, b) else 'No')