Python 寫 楊輝三角形

row=int(input("請輸入行數："))
while row>10 or row<=0:
    row=int(input("請輸入行數："))
b=[[0 for i in range(j+1)] for j in range(row)]

for i in range(row):
    for j in range(i+1):
        if i==j or j==0:
            b[i][j]=1
        else:
            b[i][j]=b[i-1][j]+b[i-1][j-1]
for m in b:
    for n in m:
        print str(n)+"\t",
    print '\n'