提出詳細
ソースコード
import sys
sys.setrecursionlimit(10 ** 6)
class unionfind:
def __init__(self, n):
self.parents = [-1 for i in range(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, y = self.find(x), self.find(y)
if x == y:
return
if self.parents[x] > self.parents[y]:
x, y = y, x
self.parents[x] = -2
self.parents[y] = x
def connectivity(self):
if len([i for i in range(26) if self.parents[i] == -2]) == 1:
return True
return False
ans = []
for i in range(int(input())):
n = int(input())
w = [input() for i in range(n)]
head = {chr(i):0 for i in range(ord('a'), ord('z') + 1)}
tail = {chr(i):0 for i in range(ord('a'), ord('z') + 1)}
for i in w:
head[i[0]] += 1
tail[i[-1]] += 1
tmp = False
for i in range(ord('a'), ord('z') + 1):
if head[chr(i)] != tail[chr(i)]:
tmp = True
break
if tmp:
ans.append('NG')
continue
if n == 1:
ans.append('OK')
continue
uf = unionfind(26)
for i in w:
if i[0] != i[-1]:
uf.union(ord(i[0]) - ord('a'), ord(i[-1]) - ord('a'))
ans.append('OK' if uf.connectivity() else 'NG')
for i, x in enumerate(ans):
print('Case #' + str(i + 1) + ':')
print(x)
提出情報
提出出力結果
テストケース情報