mod = int(1e9+7)
def add(a, b):
    c = a + b
    if c >= mod:
        c -= mod
    return c

def main():
    #N, K = map(int,raw_input().split())
    n = int(raw_input())
    
    d = n % 10
    
    if d == 3:
        print('bon')
    elif d == 0 or d == 1 or d == 6 or d == 8:
        print('pon')
    else:
        print('bon')
        
    
main()