Tuesday, June 18, 2013

unique path II@leetcode

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刷题必备书籍:Cracking the Coding Interview: 150 Programming Questions and Solutions
Follow up for "Unique Paths":
Now consider if some obstacles are added to the grids. How many unique paths would there be?
An obstacle and empty space is marked as 1 and 0 respectively in the grid.
For example,
There is one obstacle in the middle of a 3x3 grid as illustrated below.
[
  [0,0,0],
  [0,1,0],
  [0,0,0]
]
The total number of unique paths is 2.
Note: m and n will be at most 100.

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Leetcode 316. Remove Duplicate Letters

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