657. Judge Route Circle 判断线路成圆

Initially, there is a Robot at position (0, 0). Given a sequence of its moves, judge if this robot makes a circle, which means it moves back to the original place.

The move sequence is represented by a string. And each move is represent by a character. The valid robot moves are R (Right), L(Left), U (Up) and D (down). The output should be true or false representing whether the robot makes a circle.

Example 1:

Input: "UD"
Output: true

Example 2:

Input: "LL"
Output: false

  1. class Solution:
  2. def judgeCircle(self, moves):
  3. """
  4. :type moves: str
  5. :rtype: bool
  6. """
  7. res = [0,0]
  8. def o(s):
  9. if s == "L":
  10. res[0] = res[0] - 1
  11. elif s == "R":
  12. res[0] = res[0] + 1
  13. elif s == "U":
  14. res[1] = res[1] + 1
  15. elif s == "D":
  16. res[1] = res[1] - 1
  17. for i in range(0,len(moves)):
  18. o(moves[i])
  19. return res[0] == res[1] == 0






posted @ 2017-08-14 22:23  xiejunzhao  阅读(199)  评论(0编辑  收藏  举报