結果
| 問題 | No.1553 Lovely City |
| ユーザー |
 ansain
|
| 提出日時 | 2021-06-18 23:24:46 |
| 言語 | PyPy3 (7.3.15) |
| 結果 |
AC
|
| 実行時間 | 904 ms / 2,000 ms |
| コード長 | 5,539 bytes |
| コンパイル時間 | 278 ms |
| コンパイル使用メモリ | 82,796 KB |
| 実行使用メモリ | 172,388 KB |
| 最終ジャッジ日時 | 2024-06-22 21:30:15 |
| 合計ジャッジ時間 | 20,909 ms |
|
ジャッジサーバーID （参考情報） |
judge4 / judge5 |
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テストケース
テストケース表示| 入力 | 結果 | 実行時間 実行使用メモリ |
|---|---|---|
| testcase_00 | AC | 44 ms
62,656 KB |
| testcase_01 | AC | 43 ms
62,884 KB |
| testcase_02 | AC | 317 ms
130,672 KB |
| testcase_03 | AC | 54 ms
66,556 KB |
| testcase_04 | AC | 54 ms
68,160 KB |
| testcase_05 | AC | 62 ms
71,544 KB |
| testcase_06 | AC | 52 ms
66,932 KB |
| testcase_07 | AC | 51 ms
66,588 KB |
| testcase_08 | AC | 663 ms
149,592 KB |
| testcase_09 | AC | 677 ms
142,204 KB |
| testcase_10 | AC | 793 ms
154,120 KB |
| testcase_11 | AC | 628 ms
137,768 KB |
| testcase_12 | AC | 771 ms
162,132 KB |
| testcase_13 | AC | 608 ms
132,052 KB |
| testcase_14 | AC | 644 ms
150,772 KB |
| testcase_15 | AC | 651 ms
139,224 KB |
| testcase_16 | AC | 708 ms
146,748 KB |
| testcase_17 | AC | 660 ms
137,064 KB |
| testcase_18 | AC | 879 ms
171,124 KB |
| testcase_19 | AC | 896 ms
172,388 KB |
| testcase_20 | AC | 894 ms
170,740 KB |
| testcase_21 | AC | 904 ms
170,024 KB |
| testcase_22 | AC | 889 ms
170,296 KB |
| testcase_23 | AC | 887 ms
171,808 KB |
| testcase_24 | AC | 889 ms
170,096 KB |
| testcase_25 | AC | 873 ms
170,372 KB |
| testcase_26 | AC | 888 ms
170,508 KB |
| testcase_27 | AC | 877 ms
172,292 KB |
ソースコード
import sys
from collections import defaultdict, Counter, deque
from itertools import permutations, combinations, product, combinations_with_replacement, groupby, accumulate
import operator
from math import sqrt, gcd, factorial
from copy import deepcopy
# from math import isqrt, prod,comb # python3.8用(notpypy)
#from bisect import bisect_left,bisect_right
#from functools import lru_cache,reduce
#from heapq import heappush,heappop,heapify,heappushpop,heapreplace
#from networkx.utils import UnionFind
#from numba import njit, b1, i1, i4, i8, f8
#from scipy.sparse import csr_matrix
#from scipy.sparse.csgraph import shortest_path, floyd_warshall, dijkstra, bellman_ford, johnson, NegativeCycleError
# numba例 @njit(i1(i4[:], i8[:, :]),cache=True) 引数i4配列、i8 2次元配列,戻り値i1
def input(): return sys.stdin.readline().rstrip()
def divceil(n, k): return 1+(n-1)//k # n/kの切り上げを返す
def yn(hantei, yes='Yes', no='No'): print(yes if hantei else no)
class scc_graph:
def __init__(self, N):
self.N = N
self.edges = []
def csr(self):
self.start = [0]*(self.N+1)
self.elist = [0]*len(self.edges)
for e in self.edges:
self.start[e[0]+1] += 1
for i in range(1, self.N+1):
self.start[i] += self.start[i-1]
counter = self.start[:]
for e in self.edges:
self.elist[counter[e[0]]] = e[1]
counter[e[0]] += 1
def add_edge(self, v, w):
self.edges.append((v, w))
def scc_ids(self):
self.csr()
N = self.N
now_ord = group_num = 0
visited = []
low = [0]*N
order = [-1]*N
ids = [0]*N
parent = [-1]*N
stack = []
for i in range(N):
if order[i] == -1:
stack.append(i)
stack.append(i)
while stack:
v = stack.pop()
if order[v] == -1:
low[v] = order[v] = now_ord
now_ord += 1
visited.append(v)
for i in range(self.start[v], self.start[v+1]):
to = self.elist[i]
if order[to] == -1:
stack.append(to)
stack.append(to)
parent[to] = v
else:
low[v] = min(low[v], order[to])
else:
if low[v] == order[v]:
while True:
u = visited.pop()
order[u] = N
ids[u] = group_num
if u == v:
break
group_num += 1
if parent[v] != -1:
low[parent[v]] = min(low[parent[v]], low[v])
for i, x in enumerate(ids):
ids[i] = group_num-1-x
return group_num, ids
def scc(self):
group_num, ids = self.scc_ids()
groups = [[] for _ in range(group_num)]
for i, x in enumerate(ids):
groups[x].append(i)
return groups
class UnionFind():
def __init__(self, n):
self.n = n
self.parents = [-1] * n
self.group_num = n
def find(self, x):
if self.parents[x] < 0:
return x
else:
self.parents[x] = self.find(self.parents[x])
return self.parents[x]
def union(self, x, y):
x = self.find(x)
y = self.find(y)
if x == y:
return
self.group_num -= 1
if self.parents[x] > self.parents[y]:
x, y = y, x
self.parents[x] += self.parents[y]
self.parents[y] = x
def size(self, x):
return -self.parents[self.find(x)]
def same(self, x, y):
return self.find(x) == self.find(y)
def members(self, x):
root = self.find(x)
return [i for i in range(self.n) if self.find(i) == root]
def roots(self):
return [i for i, x in enumerate(self.parents) if x < 0]
def group_count(self):
return self.group_num
def all_group_members(self):
self.all_group_member = defaultdict(list)
for i in range(self.n):
self.all_group_member[self.find(i)].append(i)
return self.all_group_member
def __str__(self):
return '\n'.join('{}: {}'.format(r, self.members(r)) for r in self.roots())
def main():
n,m=map(int, input().split())
uf=UnionFind(n)
edges=[[] for i in range(n)]
for i in range(m):
a,b=map(lambda x: int(x)-1, input().split())
uf.union(a,b)
edges[a].append(b)
ans=[]
for mem in uf.all_group_members().values():
sc=scc_graph(len(mem))
memdic={mm:i for i,mm in enumerate(mem)}
memdic2={i:mm for i,mm in enumerate(mem)}
for mm in mem:
for v in edges[mm]:
sc.add_edge(memdic[mm],memdic[v])
group=sc.scc()
if all(len(gg)==1 for gg in group):
for i in range(len(group)-1):
ans.append([memdic2[group[i][0]]+1,memdic2[group[i+1][0]]+1])
else:
for i in range(len(mem)):
ans.append([mem[i]+1,mem[i-1]+1])
print(len(ans))
for aa in ans:
print(*aa)
if __name__ == '__main__':
main()