MediumNo. 0789
Escape The Ghosts — LeetCode 789 Python Solution
- Pattern
- Math and Number Theory
- Topics
- Array, Math
- Reading time
- 2 min
- Source
- leetcode.com
The problem
You are playing a simplified PAC-MAN game on an infinite 2-D grid. You start at the point [0, 0], and you are given a destination point target = [xtarget, ytarget] that you are trying to get to.
Example
- Input
- ghosts = [[1,0],[0,3]], target = [0,1]
- Output
- true
- Explanation
- You can reach the destination (0, 1) after 1 turn, while the ghosts located at (1, 0) and (0, 3) cannot catch up with you.
Python solution
class Solution:
def escapeGhosts(self, ghosts: List[List[int]], target: List[int]) -> bool:
tx, ty = target
return all(abs(tx - x) + abs(ty - y) > abs(tx) + abs(ty) for x, y in ghosts)Complexity
- Time
- O(n) or O(1)
- Space · auxiliary
- O(1)
Pattern: Math and Number Theory
Find the closed form, the invariant, or the modular identity — and skip the loop entirely. LeetCode 789. Escape The Ghosts is filed here on both counts: the reference solution below belongs to the algorithm family this hub collects, and LeetCode tags it Math.
The math and number theory guide has the Python template for the pattern and the 485 LeetCode problems that use it.
Related problems
| No. | Problem | Difficulty |
|---|---|---|
| 0048 | Rotate Image | Medium |
| 0066 | Plus One | Easy |
| 0189 | Rotate Array | Medium |
| 0204 | Count Primes | Medium |
| 0335 | Self Crossing | Hard |
| 0384 | Shuffle an Array | Medium |
Frequently asked questions
- How hard is LeetCode 789. Escape The Ghosts?
LeetCode 789. Escape The Ghosts is rated Medium on LeetCode.
- What topics does LeetCode 789. Escape The Ghosts cover?
LeetCode 789. Escape The Ghosts is tagged Array and Math on LeetCode.