0

我应该编写一个程序,它接受一串二进制代码和一个数字,并输出原始字符串汉明距离内的所有字符串。我有一个可以做所有事情的函数,但是在输出中有列表中的列表。我明白为什么会这样 - 该函数是递归的,有时它会返回一个可能值的列表。

问题是,我不知道如何更改它以输出完整的字符串。例如,对于“0000”和汉明距离“2”的字符串,我得到: ["1['100', '010', '001']", "01['10', '01']" , "001['1']"]

但我想要的是:

1100
1010
1001
0110
0101
0011

代码如下:

def hamming(num, dist):
    if dist == 0:
        return num
    else:
        outputlist = list()
        for item in range(len(num)):
            if len(num[item:]) > dist - 1:
                if num[item] == "0":
                    restoflist = hamming(num[item + 1:], dist - 1)
                    outputlist.append(num[:item] + "1" + str(restoflist))
                else:
                    restoflist = hamming(num[item + 1:], dist - 1)
                    outputlist.append(num[:item] + "0" + str(restoflist))                
        return outputlist
4

2 回答 2

1

如果您遍历返回的列表,hamming您应该能够以正确的方式将字符串附加在一起 ​​- 如下所示:

def hamming(num, dist):
    if dist == 0:
        return num
    else:
        outputlist = list()
        for item in range(len(num)):
            if len(num[item:]) > dist - 1:
                if num[item] == "0":
                    restoflist = hamming(num[item + 1:], dist - 1)
                    if type(restoflist) is not str
                        for rest in restoflist:
                            outputlist.append(num[:item] + "1" + str(rest))
                    else
                        outputlist.append(num[:item] + "1" + str(restoflist))
                else:
                    restoflist = hamming(num[item + 1:], dist - 1)
                    if type(restoflist) is not str
                        for rest in restoflist:
                            outputlist.append(num[:item] + "0" + str(rest))
                    else
                        outputlist.append(num[:item] + "0" + str(restoflist))                
    return outputlist
于 2014-02-27T15:02:39.653 回答
0

[num]您可以通过在基本情况下返回而不是修复它,在一般情况下,使用and而不是num组合递归调用的结果:mapextendappend

def hamming(num, dist):
    if dist == 0:
        return [num]
    else:
        outputlist = list()
        for item in range(len(num)):
            if len(num[item:]) > dist - 1:
                if num[item] == "0":
                    restoflist = hamming(num[item + 1:], dist - 1)
                    outputlist.extend(map(lambda x: num[:item] + "1" + x, restoflist))
                else:
                    restoflist = hamming(num[item + 1:], dist - 1)
                    outputlist.extend(map(lambda x: num[:item] + "0" + x, restoflist))                
        return outputlist

>>> hamming('0000', 2)
['1100', '1010', '1001', '0110', '0101', '0011']
>>> 
于 2014-02-27T15:08:09.710 回答