python
class Solution:
def maximalRectangle(self, matrix: List[List[str]]) -> int:
def hist(heights):
stack,ans=[],0
for i,h in enumerate(heights+[0]):
while stack and heights[stack[-1]]>=h:
H=heights[stack.pop()]
W=i if not stack else i-stack[-1]-1
ans=max(ans,H*W)
stack.append(i)
return ans
if not matrix or not matrix[0]: return 0
m,n,ans=len(matrix[0]),len(matrix),0
row=[0]*m
for i in range(n):
for j in range(m):
row[j]=0 if matrix[i][j]=='0' else row[j]+1
ans=max(ans,hist(row))
return ans二维单调栈
递增栈