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  • 62. Unique Paths(矩阵的总路径数)

    A robot is located at the top-left corner of a m x n grid (marked 'Start' in the diagram below).

    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).

    How many possible unique paths are there?


    Above is a 7 x 3 grid. How many possible unique paths are there?

    Note: m and n will be at most 100.

    Example 1:

    Input: m = 3, n = 2
    Output: 3
    Explanation:
    From the top-left corner, there are a total of 3 ways to reach the bottom-right corner:
    1. Right -> Right -> Down
    2. Right -> Down -> Right
    3. Down -> Right -> Right
    

    Example 2:

    Input: m = 7, n = 3
    Output: 28

    题目描述:统计从矩阵左上角到右下角的路径总数,每次只能向右或者向下移动
    分析:先举例再总结规律,第一列的路径只能有一条,第一行同理。dp[1][1] 就有两条,上面一条,左边一条。所以得到公式 dp[i][j]=dp[i-1][j]+dp[i][j-1]

    
    
    苟有恒,何必三更眠五更起;最无益,莫过一日暴十日寒。
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  • 原文地址:https://www.cnblogs.com/shaer/p/10520384.html
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