Task:

You have to write a function pattern which creates the following pattern up to n/2 number of lines.

• If n <= 1 then it should return "" (i.e. empty string).
• If any odd number is passed as argument then the pattern should last up to the largest even number which is smaller than the passed odd number.

Examples:

n = 8:

22
4444
666666
88888888

n = 5:

22
4444

Note: There are no spaces in the pattern.

Hint: Use \n in string to jump to next line.