n = int(input())
s = input()
x = 0
ng = False
for c in s:
    if c == 'Q':
        x += 1
    if c == 'H' or c == '9':
        ng = True
if x == 1 and not ng:
    print(s)
elif x == n:
    k = 2
    while int(pow(k,k)) < n:
        k += 1
    if int(pow(k,k)) == n:
        print('Q'*k)
    else:
        print(-1)
else:
    print(-1)