leetpycode/medium/find_minimum_time_to_reach_last_room_ii.py

28 lines
1.1 KiB
Python

# https://leetcode.com/problems/find-minimum-time-to-reach-last-room-ii
from typing import List, Tuple
import heapq
class Solution:
def minTimeToReach(self, moveTime: List[List[int]]) -> int:
n, m = len(moveTime), len(moveTime[0])
dirs: List[Tuple[int, int]] = [(-1, 0), (1, 0), (0, -1), (0, 1)]
min_time = [[float('inf')] * m for _ in range(n)]
min_time[0][0] = 0
heap: List[Tuple[int, int, int, int]] = [(0, 0, 0, 1)]
while heap:
curr_time, y, x, moves = heapq.heappop(heap)
if (y, x) == (n - 1, m - 1):
return curr_time
if curr_time > min_time[y][x]:
continue
for dy, dx in dirs:
ny, nx = y + dy, x + dx
if 0 <= ny < n and 0 <= nx < m:
start_time = max(curr_time, moveTime[ny][nx])
arrival_time = start_time + (2 if moves % 2 == 0 else 1)
if arrival_time < min_time[ny][nx]:
min_time[ny][nx] = arrival_time
heapq.heappush(heap, (arrival_time, ny, nx, moves + 1))
return -1