leetcode:165. compare version numbers

题目概述

Compare two version numbers version1 and version2.
If *version1* > *version2* return 1; if *version1* < *version2* return -1;otherwise return 0.

You may assume that the version strings are non-empty and contain only digits and the . character.

The . character does not represent a decimal point and is used to separate number sequences.

For instance, 2.5 is not “two and a half” or “half way to version three”, it is the fifth second-level revision of the second first-level revision.

You may assume the default revision number for each level of a version number to be 0. For example, version number 3.4 has a revision number of 3 and 4 for its first and second level revision number. Its third and fourth level revision number are both 0.

Example 1:

1
2

Input: version1 = "0.1", version2 = "1.1"
Output: -1

Example 2:

1
2

Input: version1 = "1.0.1", version2 = "1"
Output: 1

Example 3:

1
2

Input: version1 = "7.5.2.4", version2 = "7.5.3"
Output: -1

Example 4:

1
2
3

Input: version1 = "1.01", version2 = "1.001"
Output: 0
Explanation: Ignoring leading zeroes, both “01” and “001" represent the same number “1”

Example 5:

1
2
3

Input: version1 = "1.0", version2 = "1.0.0"
Output: 0
Explanation: The first version number does not have a third level revision number, which means its third level revision number is default to "0"

Note:

1. Version strings are composed of numeric strings separated by dots . and this numeric strings may have leading zeroes.
2. Version strings do not start or end with dots, and they will not be two consecutive dots.

这题其实不难，本质上就是把字符串根据’.’进行切割后形成两个数组，然后对两个数组的元素进行逐一比较即可。

代码实现

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23

class :
    def compareVersion(self, version1: 'str', version2: 'str') -> 'int':
        list1 = version1.split('.')
        list2 = version2.split('.')
        maxNum = min(len(list1), len(list2))
        for i in range(maxNum):
            if int(list1[i]) > int(list2[i]):
                return 1
            elif int(list1[i]) < int(list2[i]):
                return -1

        if len(list1) > len(list2):
            for i in range(maxNum, len(list1)):
                if int(list1[i]) > 0:
                    return 1
            return 0
        elif len(list1) == len(list2):
            return 0
        else:
            for i in range(maxNum, len(list2)):
                if int(list2[i]) > 0:
                    return -1
            return 0