Merkkijono

def main(n):
    if n == 1:
        print('a')
        return 
    if n == 2:
        print('bab')

    aakkoset = 'bcdefghijklmnopqrs'
    output = ' a '
    for i in range(n):
        output = aakkoset[i].join(output)
    print(output.strip())

if __name__ == '__main__':
    n = int(input())
    main(n-1)

Test 1

Verdict: ACCEPTED

Test 2

Verdict: WRONG ANSWER

Test 3

Verdict: WRONG ANSWER

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: ACCEPTED

Test 13

Verdict: ACCEPTED

Test 14

Verdict: ACCEPTED

Test 15

Verdict: ACCEPTED

Test 16

Verdict: ACCEPTED