题解 | #矩阵的最小路径和#

dp大法好

class Solution:
    def minPathSum(self , matrix ):
        # write code here
        n = len(matrix)
        m = len(matrix[0])
        dp = [[-1 for i in range(m)]for i in range(n)]
        dp[0][0]=matrix[0][0]
        for i in range(1,n):
            dp[i][0] = dp[i-1][0]+matrix[i][0]
        for j in range(1,m):
            dp[0][j] = dp[0][j-1]+matrix[0][j]
        for i in range(1,n):
            for j in range(1,m):
                dp[i][j] = min(dp[i-1][j],dp[i][j-1])+matrix[i][j]

        return dp[n-1][m-1]