60 lines
1.1 KiB
Markdown
60 lines
1.1 KiB
Markdown
---
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layout: page
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title: Unique Paths
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last_solved: 2020-06-29
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category: dp
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leetcode_url: https://leetcode.com/problems/unique-paths/submissions/
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status: Solved
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---
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Problem
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-------
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```
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A robot is located at the top-left corner of a m x n grid (marked 'Start' in the diagram below).
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The robot can only move either down or right at any point in time. The robot is trying to reach the bottom-right corner of the grid (marked 'Finish' in the diagram below).
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How many possible unique paths are there?
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Above is a 7 x 3 grid. How many possible unique paths are there?
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Example 1:
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Input: m = 3, n = 2
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Output: 3
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Explanation:
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From the top-left corner, there are a total of 3 ways to reach the bottom-right corner:
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1. Right -> Right -> Down
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2. Right -> Down -> Right
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3. Down -> Right -> Right
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Example 2:
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Input: m = 7, n = 3
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Output: 28
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```
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Solution
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----------
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{% highlight python %}
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def uniquePaths(self, m: int, n: int) -> int:
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dp = [[1]*(n) for x in range(m)]
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for i in range(1, m):
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for j in range(1, n):
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dp[i][j] = dp[i][j-1] + dp[i-1][j]
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print(dp)
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return dp[-1][-1]
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{% endhighlight %}
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![image1]() |