from __future__ import annotations
import types
from typing import Generator, Iterable

def suffixes( iter_in: Iterable[ int ] ) \
        -> Generator[ Iterable[ int ], None, None ]:
    list_in = list( iter_in )
    for i in range( len( list_in ), -1, -1 ):
        yield list_in[ i : ]

def suffix_sum( iter_in: Iterable[ int ] ) \
        -> Generator[ int, None, None ]:
    count = 0
    for item in reversed( list( iter_in ) ):
        count += item
        yield count

import run_tests