[Python] 2進数と10進数を相互変換する方法を解説

# 2進数の文字列
binary_string = "1011"
# 2進数から10進数に変換
decimal_number = int(binary_string, 2)
print(decimal_number)

11

# 10進数の整数
decimal_number = 11
# 10進数から2進数に変換
binary_string = bin(decimal_number)
print(binary_string)

0b1011

# 2つの整数
a = 5  # 2進数で101
b = 3  # 2進数で011
# ビット演算
and_result = a & b
or_result = a | b
xor_result = a ^ b
print(f"AND: {and_result}, OR: {or_result}, XOR: {xor_result}")

AND: 1, OR: 7, XOR: 6

import heapq
from collections import defaultdict
# ハフマンノードのクラス
class Node:
    def __init__(self, char, freq):
        self.char = char
        self.freq = freq
        self.left = None
        self.right = None
    def __lt__(self, other):
        return self.freq < other.freq
# ハフマン符号化の関数
def huffman_coding(data):
    frequency = defaultdict(int)
    for char in data:
        frequency[char] += 1
    heap = [Node(char, freq) for char, freq in frequency.items()]
    heapq.heapify(heap)
    while len(heap) > 1:
        left = heapq.heappop(heap)
        right = heapq.heappop(heap)
        merged = Node(None, left.freq + right.freq)
        merged.left = left
        merged.right = right
        heapq.heappush(heap, merged)
    return heap[0]
# 使用例
data = "hello huffman"
huffman_tree = huffman_coding(data)

def xor_encrypt_decrypt(input_string, key):
    return ''.join(chr(ord(c) ^ key) for c in input_string)
# 使用例
original_text = "hello"
key = 123  # 任意の整数
encrypted_text = xor_encrypt_decrypt(original_text, key)
decrypted_text = xor_encrypt_decrypt(encrypted_text, key)
print(f"Encrypted: {encrypted_text}, Decrypted: {decrypted_text}")

Encrypted: , Decrypted: hello