class Solution:
def generate(self, numRows: int) -> List[List[int]]:
#官方解法
res = []
for i in range(numRows):
tmp = []
for j in range(i+1):
if j==0 or j==i:
tmp.append(1)
else:
tmp.append(res[i-1][j-1]+res[i-1][j])
res.append(tmp)
return res
#Mine
if numRows==0:
return []
if numRows==1:
return [[1]]
if numRows==2:
return [[1],[1,1]]
res=[[1],[1,1]]
for _ in range(2,numRows):
tmp = [1,1]
for i in range(len(res[-1])-1):
num = res[-1][i]+res[-1][i+1]
tmp.insert(i+1,num)
res.append(tmp)
return res
总结:杨辉三角,找规律就行。num = res[-1][i]+res[-1][i+1]