class Solution:
def minimumTotal(self, triangle: List[List[int]]) -> int:
dp = triangle[-1]
for i in range(len(triangle)-2, -1, -1): #自底向上,对三角形的每行
for j in range(len(triangle[i])): #从左到右,对三角形该行的每个位置
dp[j] = min(dp[j], dp[j+1]) + triangle[i][j]
return dp[0]