題目描述

程式設計實現將一個N進位制數轉換成M進位制數。

問題分析

將N進位制數轉換為M進位制數的一個直接的方法就是將N進位制數首先轉換為十進位制數，再從十進位制數往M進位制轉換。這樣相當於把十進位制當做一箇中間狀態來實現N進位制到M進位制的轉換，很大程度上簡化了問題。

程式碼實現

方法一：可實現任意進位制轉換

#!/usr/bin/env python
# -*- coding:utf-8 -*-
# Name: demo27.py
# Author: zhuzhuzhu   time:2018/5/29
# Connect: [email protected]
 

# Desc : 將N進位制數轉換為M進位制數
# Version：python3


def conversion_num(num, src, dest):
    rtn = ''
    # 1、校驗源（N進位制）和目標（M進位制）是否相同
    if src == dest:
        rtn = num
    # 2、轉成10進位制#
    if src != 10:
        num_str = str(num)
        # 將列表翻轉
        num_str = num_str[::-1]
        exe_num = 0
        dec_num = 0
 

        # 從最後一位數開始
        for num_char in num_str:
            # 十六進位制處理
            if num_char == 'A':
                num_char = '10'
            elif num_char == 'B':
                num_char = '11'
            elif num_char == 'C':
                num_char = '12'
            elif num_char == 'D'
 
:
                num_char = '13'
            elif num_char == 'E':
                num_char = '14'
            elif num_char == 'F':
                num_char = '15'

            num_int = int(num_char)
            if exe_num == 0:
                dec_num += num_int
            else:
                dec_num += src ** exe_num * num_int
            exe_num += 1
        # 得到給定數字的十進位制形式
        num = dec_num
    # 3、轉成目標進位制
    # 判斷目標進位制是否為十進位制
    if dest == 10:
        rtn = num
    else:
        num = int(num)
        while True:
            divisor = num // dest
            remainder = num % dest
            # 十六進位制處理
            if remainder == 10:
                remainder = 'A'
            elif remainder == 11:
                remainder = 'B'
            elif remainder == 12:
                remainder = 'C'
            elif remainder == 13:
                remainder = 'D'
            elif remainder == 14:
                remainder = 'E'
            elif remainder == 15:
                remainder = 'F'
            rtn = str(remainder) + rtn
            if divisor <= 0:
                break
            else:
                num = divisor
    # 4、處理空的字串
    if rtn == '':
        rtn = '0'
    return rtn


new_num = conversion_num('011', 2, 10)
print(new_num)

方法二：利用python內建函式（僅適用於目標進製為二進位制，八進位制，十六進位制的情況）

def conversion_num(num, src, dest):
    rtn = ''
    # 1、校驗源和目標是否相同
    if src == dest:
        rtn = num
    # 2、轉成10進位制
    if src != 10:
        dec_num = 0
        if src == 2:
            dec_num = int(num, 2)
        elif src == 8:
            dec_num = int(num, 8)
        elif src == 16:
            dec_num = int(num, 16)
        num = dec_num
    # 3、轉成目標進位制
    if dest == 10:
        rtn = num
    else:
        if dest == 2:
            rtn = bin(num)
        elif dest == 8:
            rtn = oct(num)
        elif dest == 16:
            rtn = hex(num)
    # 4、處理空的字串
    if rtn == '':
        rtn = '0'
    return rtn


new_num = conversion_num('111111', 2, 16)
print(new_num)

說明