cp_library/alg/iter/iargsort_fn.py

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• Last update: 2025-03-30 20:17:47+09:00

Depends on

• cp_library/bit/pack_sm_fn.py

Code

import cp_library.alg.iter.__header__
from cp_library.bit.pack_sm_fn import pack_sm

def iargsort(A: list[int], reverse=False):
    s, m = pack_sm(len(A))
    if reverse:
        for i,a in enumerate(A): A[i] = a<<s|i^m
        A.sort(reverse=True)
        for i,a in enumerate(A): A[i] = (a^m)&m
    else:
        for i,a in enumerate(A): A[i] = a<<s|i
        A.sort()
        for i,a in enumerate(A): A[i] = a&m
    return A

'''
╺━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━╸
             https://kobejean.github.io/cp-library               
'''


def pack_sm(N: int):
    s = N.bit_length()
    return s, (1<<s)-1

def pack_enc(a: int, b: int, s: int):
    return a << s | b
    
def pack_dec(ab: int, s: int, m: int):
    return ab >> s, ab & m

def pack_indices(A, s):
    return [a << s | i for i,a in enumerate(A)]

def iargsort(A: list[int], reverse=False):
    s, m = pack_sm(len(A))
    if reverse:
        for i,a in enumerate(A): A[i] = a<<s|i^m
        A.sort(reverse=True)
        for i,a in enumerate(A): A[i] = (a^m)&m
    else:
        for i,a in enumerate(A): A[i] = a<<s|i
        A.sort()
        for i,a in enumerate(A): A[i] = a&m
    return A

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