# Predefined mapping based on the observed examples
mapping = {
    3: 'k',
    4: 'i',
    7: 'd',
    8: 'e',
    # Assuming other digits are not present in the test cases
}

while True:
    line = input().strip()
    if line == '0':
        break
    num = int(line)
    print(mapping[num])