Task:

• Complete the pattern using the special character:

  ■ □

• In this kata, we need draw a Double-Spiral.

Rules:

• Parameter m and n It means m rows and n columns, ■ and □ composition graphics of The Double-Spiral, m>0, odd number, n>1, even number.
• Return a string, Connect each line by '\n'.
• abs(m - n) = 1

Examples:

m = 1, n = 2

(Please do not mind the black stripes, this is codewars description display effect, not perfect)

□■

m = 3, n = 2

□□
□■
■■

m = 3, n = 4

■□□□
■□■□
■■■□

m = 5, n = 4

■■■■
■□□□
■□■□
■■■□
□□□□

m = 5, n = 6

□■■■■■
□■□□□■
□■□■□■
□■■■□■
□□□□□■

m = 7, n = 6

□□□□□□
□■■■■■
□■□□□■
□■□■□■
□■■■□■
□□□□□■
■■■■■■