Python program to show diamond pattern with 2n-1 lines

Suppose we have a number n. We have to draw a diamond pattern with asterisks with 2n-1 lines. First 1 to n lines contain 1 to n number of asterisks, and next they are decreasing from n-1 to 1.

So, if the input is like n = 5, then the output will be

    *
   * *
  * * *
 * * * *
* * * * *
 * * * *
  * * *
   * *
    *

To solve this, we will follow these steps −

for i in range 1 to n, do
- print a block '* ' i times and print it in justified format in center with (2*n-1) characters space in each line
for i in range n-1 to 0, decrease by 1, do
- print a block '* ' i times and print it in justified format in center with (2*n-1) characters space in each line

Example

Let us see the following implementation to get better understanding

def solve(n):
   for i in range(1,n+1):
      print(('* '*i).center(2*n-1))
   for i in range(n-1,0, -1):
      print(('* '*i).center(2*n-1))

n = 10
solve(n)

Input

Output

         *
        * *
       * * *
      * * * *
     * * * * *
    * * * * * *
   * * * * * * *
  * * * * * * * *
 * * * * * * * * *
* * * * * * * * * *
 * * * * * * * * *
  * * * * * * * *
   * * * * * * *
    * * * * * *
     * * * * *
      * * * *
       * * *
        * *
         *