小黑享受思考心流:64.最小路径和

小黑代码

class Solution:
    def minPathSum(self, grid: List[List[int]]) -> int:
        # 数组的长和宽
        m = len(grid)
        n = len(grid[0])
        # 初始化动态规划数组
        dp = [[0]*n for _ in range(m)]
        dp[0][0] = grid[0][0]
        for i in range(m):
            for j in range(n):
                # i j 都等于0
                if not(i+j):
                    continue
                if not i:
                    dp[i][j] = dp[i][j-1]
                elif not j:
                    dp[i][j] = dp[i-1][j]
                else:
                    dp[i][j] = min(dp[i][j-1], dp[i-1][j])
                dp[i][j] += grid[i][j]
        return dp[m-1][n-1]