import random
from string import ascii_uppercase as alphabet
zipf = [1/x for x in range(1, 1+26)]


def zipf_string(length):
    letters = random.choices(alphabet, weights=zipf, k=length)
    return ''.join(letters)

def sizes_to_test():
    yield from range(1, 10)
    m = 10
    while m < 100_000:
        yield m
        m += m // 2 + 1

def do_timings():
    import pyperf
    runner = pyperf.Runner()

    # silence the warnings
    runner.parse_args()
    runner.args.quiet = True
    runner._process_priority = lambda *args: None

    haystack = zipf_string(10**6)
    for m in sizes_to_test():
        runner.timeit(f"needle={m}",
                      setup="needle = zipf_string(m); i = random.randrange(1000); substack = haystack[i:]",
                      stmt="needle in substack",
                      globals=locals() | globals())

if __name__ == "__main__":
    do_timings()