結果

問題 No.2764 Warp Drive Spacecraft
ユーザー LyricalMaestro
提出日時 2025-01-03 02:26:00
言語 PyPy3
(7.3.15)
結果
AC  
実行時間 2,051 ms / 3,000 ms
コード長 2,894 bytes
コンパイル時間 335 ms
コンパイル使用メモリ 82,560 KB
実行使用メモリ 186,152 KB
最終ジャッジ日時 2025-01-03 02:26:38
合計ジャッジ時間 35,944 ms
ジャッジサーバーID
(参考情報)
judge2 / judge4
このコードへのチャレンジ
(要ログイン)
ファイルパターン 結果
sample AC * 4
other AC * 35
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 #
プレゼンテーションモードにする

## https://yukicoder.me/problems/no/2764
import heapq
from collections import deque
MAX_INT = 10 ** 18
def dijkstra(N, next_nodes, src):
fix = [MAX_INT] * N
seen = [MAX_INT] * N
seen[src] = 0
queue = []
heapq.heappush(queue, (0, src))
while len(queue) > 0:
cost, v = heapq.heappop(queue)
if fix[v] < MAX_INT:
continue
fix[v] = cost
for w, t in next_nodes[v]:
if fix[w] < MAX_INT:
continue
new_cost = t + cost
if seen[w] > new_cost:
seen[w] = new_cost
heapq.heappush(queue, (new_cost, w))
return fix
def main():
N, M = map(int, input().split())
W = list(map(int, input().split()))
next_nodes = [[] for _ in range(N)]
for _ in range(M):
u, v, t = map(int, input().split())
next_nodes[u - 1].append((v - 1, t))
next_nodes[v - 1].append((u - 1, t))
dists_from_s = dijkstra(N, next_nodes, 0)
dists_from_t = dijkstra(N, next_nodes, N - 1)
lines_w = {}
for i in range(N):
if dists_from_s[i] < MAX_INT:
if W[i] not in lines_w:
lines_w[W[i]] = dists_from_s[i]
else:
lines_w[W[i]] = min(lines_w[W[i]], dists_from_s[i])
lines = [(w, d) for w, d in lines_w.items()]
lines.sort(key=lambda x : x[0], reverse=True)
def compare(p1, p0):
if p1[0] * p0[1] > p1[1] * p0[0]:
return 1
elif p1[0] * p0[1] < p1[1] * p0[0]:
return -1
else:
return 0
# convex hull trick
stack = deque()
for w, d in lines:
while len(stack) > 0:
w0, d0, p0 = stack[-1]
p1 = (d - d0, w0 - w)
# p1 > p0
if compare(p1, p0) == 0:
stack.pop()
break
elif compare(p1, p0) < 0:
stack.pop()
else:
break
if len(stack) == 0:
stack.append((w, d, (0, 1)))
else:
stack.append((w, d, p1))
intervals = []
while len(stack) > 0:
intervals.append(stack.popleft())
answer = dists_from_s[N - 1]
for i in range(N):
if dists_from_t[i] < MAX_INT:
w = W[i]
low = 0
high = len(intervals) - 1
while high - low > 1:
mid = (high + low) // 2
if compare((w, 1), intervals[mid][2]) >= 0:
low = mid
else:
high = mid
if compare((w, 1), intervals[high][2]) >= 0:
v = high
else:
v = low
w0, d0, _ = intervals[v]
ans = w * w0 + d0 + dists_from_t[i]
answer = min(answer, ans)
print(answer)
if __name__ == "__main__":
main()
הההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההה
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
0