键盘就收数字n ,输出2*n+1行的菱形

如：n=2

打印为：  *

           ***

             *

代码为：

1 def printUpTriangle(x,y): 2     print(" "*(y+1-x)+"*"*(2*x-1)+" "*(y+1-x)) 3  4 def printDownTriangle(x,y): 5     print(" "*(x-y-1)+"*"*(2*((2*y+1)-x)+1)+" "*(x-y-1)) 6  7  8 n = int(raw_input("please input num: ")) 9 10 for i in range(1,(2*n+2)):11     if(i<=n):12         printUpTriangle(i,n)13     elif(i==(n+1)):14         print("*"*(2*n+1))15     elif(i>n+1):16         printDownTriangle(i,n)