# Read input until 0 is encountered
digit_map = {
    3: 'k',
    4: 'i',
    7: 'd',
    8: 'e'
}

import sys

for line in sys.stdin:
    num = int(line.strip())
    if num == 0:
        break
    if num in digit_map:
        print(digit_map[num])