Hackerrank Door mat

doormat.py

# Enter your code here. Read input from STDIN. Print output to STDOUT
n, m = input().split()
n = int(n)
m = int(m)

extra = 0
reversed_iteration = False
tracker = []

for i in range(0, n):
    if int(n/2) == i:
        print('WELCOME'.center(m, '-'))
        reversed_iteration = True
    else:
        if reversed_iteration:
            print(tracker[n - i - 1])
        else:
            decoration = '.|.' * (i + extra + 1)
            print(decoration.center(m, '-'))
            tracker.append(decoration.center(m, '-'))
            extra += 1