結果

問題 No.1612 I hate Construct a Palindrome
ユーザー mkawa2mkawa2
提出日時 2024-06-13 23:53:27
言語 PyPy3
(7.3.15)
結果
AC  
実行時間 802 ms / 2,000 ms
コード長 1,692 bytes
コンパイル時間 648 ms
コンパイル使用メモリ 82,524 KB
実行使用メモリ 164,492 KB
最終ジャッジ日時 2024-06-13 23:53:42
合計ジャッジ時間 12,487 ms
ジャッジサーバーID
(参考情報)
judge5 / judge2
このコードへのチャレンジ
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ファイルパターン 結果
sample AC * 3
other AC * 36
権限があれば一括ダウンロードができます

ソースコード

diff #

import sys

# sys.setrecursionlimit(1000006)
# 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

from collections import deque

n, m = LI()
to = [[] for _ in range(n)]
cc = []
uv = []
for i in range(m):
    u, v, c = SI().split()
    u = int1(u)
    v = int1(v)
    c = ord(c)-97
    to[u].append((v, i))
    to[v].append((u, i))
    cc.append(c)
    uv.append(u ^ v)

q = deque()
# dp = [[0]*27 for _ in range(n)]
ee = [[None]*27 for _ in range(n)]
for v, i in to[0]:
    c = cc[i]
    # dp[v][c] = 1
    ee[v][c] = (0, -1, i)
    q.append((v, c))

while q:
    u, c = q.popleft()
    for v, i in to[u]:
        nc = c
        if c != cc[i]: nc = 26
        if ee[v][nc]: continue
        # dp[v][nc] = 1
        ee[v][nc] = (u,c,i)
        q.append((v, nc))

# p2D(ee)
if ee[-1][-1] == None:
    print(-1)
    exit()

ii = []
u = n-1
c = 26
while c!=-1:
    u,c,i = ee[u][c]
    ii.append(i)

s=[cc[i] for i in ii]
if s==s[::-1]:
    ii.append(ii[-1])
    ii.append(ii[-1])

print(len(ii))
for i in ii[::-1]:print(i+1)
0