for i in range(1,10):
for j in range(1,i+1):
print("{}*{}={}".format(j,i,i*j),end="\t")
print()
输出圣诞树
for i in range(1,11):
for j in range(1,11-i):
print(" ",end="")
for k in range(1,2*i):
print("$",end="")
print()
#下面是树干
s="***"
for l in range(1,8):
print((s).center(20))