Unique Paths
There is a robot on an m x n grid. The robot is initially located at the top-left corner (i.e., grid[0][0]). The robot tries to move to the bottom-right corner (i.e., grid[m - 1][n - 1]). The robot can only move either down or right at any point in time.
Given the two integers m and n, return the number of possible unique paths that the robot can take to reach the bottom-right corner.
class Solution:
def uniquePaths(self, m, n):
dp = [[1]*n for i in range(m)]
for i, j in product(range(1, m), range(1, n)):
dp[i][j] = dp[i-1][j] + dp[i][j-1]
return dp[-1][-1]Related Problems
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