123jimin / ckp

Pure Python implementations of competitive programming algorithms.

CKP - Code Kit for Python

• 한국어

Caution

This library is currently work-in-progress. Any API may change.

CKP is a collection of no-dependency, pure Python implementations of various algorithms for competitive programming.

CKP aims to provide versatile interface, without hurting performance.

CKP is compatible with impacker, a tool for packing a code and its dependencies into one file. Therefore, CKP can be used for online judges which cannot accept more than one source file.

Examples

For the full list of functions, refer to the document (TO-DO).

Segment Tree

from ckp.data_structure import SimpleSegmentTree
from ckp.number_theory import PrimeSieve

tree = SimpleSegmentTree(list(PrimeSieve(10_000_000).primes()), op=lambda x,y: (x*y)%1_000_000, e=1)
print(len(tree)) # 664579
print(tree.reduce()) # 668970 (last 6 digits of product of all primes <= 10_000_000)
print(tree.reduce_range(12345, 67890)) # 830967

tree[20000] = 100
print(tree.reduce_range(12345, 67890)) # 596900

Factoring

from ckp.number_theory import factor

# [3250204337, 9181271329]
print(sorted(factor(29841007892689553873)))

Notes

Implementations of SortedList and SortedDict are based on sortedcontainers (https://github.com/grantjenks/python-sortedcontainers), which is originally under Apache License, version 2.0 (http://www.apache.org/licenses/LICENSE-2.0).

Using CKP for purposes other than competitive programming is not recommended. This library is (and must be) written in pure Python, which is a huge restriction on performance.

If your application doesn't require you to write code in pure Python, then please implement your own C extensions, use another library, or use another language.

To-Do List

• automata
• data_structure
  • disjoint_set
  • graph
  • segment_tree
  • sorted_containers
• fourier
  • complex
  • ntt
• geometry
  • circumcircle
  • circumsphere
  • convex_hull
  • delaunay
• graph_theory
  • bipartite_matching
  • ford_fulkerson
  • strongly_connected_components
• language
• linear_algebra
• nimber
• number_theory
• polynomial
• string
  • kmp
  • suffix_array

Usage

Installing

I strongly recommend using Poetry.

poetry add git+https://github.com/123jimin/ckp.git

Using

Write your code using CKP, like this:

from ckp.number_theory.primality_test import is_prime_naive

N = int(input())
print(is_prime_naive(N))

Run your code like this:

poetry run python test.py

Packing

To pack CKP into the source code, install impacker.

poetry add git+https://github.com/123jimin/impacker.git

Pack CKP by using impacker (assuming that your source code's name is code.py, and you wish the result file's name to be out.py):

poetry run python -m impacker code.py out.py

out.py will contain the packed source code, submittable to online judges:

import math

# From primality_test.py
def is_prime_naive(n: int) -> bool:
    """
        Naive primality testing.
        - Time: `O(sqrt(n))`
    """
    if n < 100:
        return n in {2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97}
    if n % 2 == 0 or n % 3 == 0 or n % 5 == 0 or (n % 7 == 0) or (n % 11 == 0):
        return False
    for p in range(13, math.isqrt(n) + 1, 6):
        if n % p == 0 or n % (p + 4) == 0:
            return False
    return True

# From test.py
N = int(input())
print(is_prime_naive(N))