Given a string path
, where path[i] = 'N'
, 'S'
, 'E'
or 'W'
, each representing moving one unit north, south, east, or west, respectively. You start at the origin (0, 0)
on a 2D plane and walk on the path specified by path
.
Return true
if the path crosses itself at any point, that is, if at any time you are on a location you have previously visited. Return false
otherwise.
Example 1:
Input: path = "NES"
Output: false
Explanation: Notice that the path doesn't cross any point more than once.
Example 2:
Input: path = "NESWW"
Output: true
Explanation: Notice that the path visits the origin twice.
Constraints:
-
1 <= path.length <= 104
-
path[i]
is either'N'
,'S'
,'E'
, or'W'
.
SOLUTION:
class Solution:
def isPathCrossing(self, path: str) -> bool:
x = 0
y = 0
visited = set()
visited.add((x, y))
for c in path:
if c == 'N':
y += 1
if c == 'E':
x += 1
if c == 'S':
y -= 1
if c == 'W':
x -= 1
if (x, y) in visited:
return True
visited.add((x, y))
return False
Top comments (0)