动态规划

#
# 
# @param m int整型 
# @param n int整型 
# @return int整型
#
class Solution:
    def uniquePaths(self , m , n ):
        # write code here

        dp = [[0 for _ in range(n)] for _ in range(m)]
        for i in range(0, m):
            dp[i][0] = 1
        for j in range(0, n):
            dp[0][j] = 1
        for i in range(1, m):
            for j in range(1, n):
                dp[i][j] = dp[i-1][j] + dp[i][j-1]
        return dp[m-1][n-1]