用Python实现图灵机

用Python实现图灵机

图灵机是计算理论中的经典模型，能够可靠地模拟任何计算机算法。本文将介绍如何用Python实现一个简单的图灵机。

首先，我们需要定义图灵机的状态。一个图灵机由状态、转移函数、输入、输出以及当前状态组成。我们可以用一个类来表示它：

class TuringMachine:
    def __init__(self, states, input_alphabet, tape_alphabet, blank_symbol, transitions, initial_state, accepting_states, rejecting_states):
        self.states = states
        self.input_alphabet = input_alphabet
        self.tape_alphabet = tape_alphabet
        self.blank_symbol = blank_symbol
        self.transitions = transitions
        self.current_state = initial_state
        self.accepting_states = accepting_states
        self.rejecting_states = rejecting_states
        self.tape = []

    def run(self, input_str):
        self.tape = list(input_str) + [self.blank_symbol]
        head_position = 0