题目描述
给定一个包含非负整数的 m x n 网格,请找出一条从左上角到右下角的路径,使得路径上的数字总和为最小。
说明:每次只能向下或者向右移动一步。
示例:
输入:
[
[1,3,1],
[1,5,1],
[4,2,1]
]
输出: 7
解释: 因为路径 1→3→1→1→1 的总和最小。
思路
代码
class Solution():
def minPathSum(self,grid:[[int]]) ->int:
m = len(grid)
n = len(grid[0])
for i in range(0,m):
for j in range(0,n):
if i == j == 0:
continue
elif i == 0:
grid[i][j] = grid[i][j-1] + grid[i][j]
elif j == 0:
grid[i][j] = grid[i-1][j] + grid[i][j]
else:
grid[i][j] = min(grid[i][j-1],grid[i-1][j]) + grid[i][j]
return grid[-1][-1]
test = Solution()
test.minPathSum([
[1,3,1],
[1,5,1],
[4,2,1]
])