def triangle(n):

L=[]

for i in range(n):

if i==0:

L.append([1])

elif i==1:

L.append([1,1])

else:

y =[]

for j in range(i+1):

if j==0 or j==i:

y.append(1)

else:

y.append(L[i-1][j]+L[i-1][j-1])

L.append(y)

return L

n=int(input("请输入杨辉三角打印的行数："))

x=triangle(n)

for i in range(len(x)):

s=str(x[i])

print(s.center(n*10))