leetcode中等165比较版本号

Posted 2021-06-06 qq_40707462

思路一：用split函数分割成数组。然后比较

class Solution(object):
    def compareVersion(self, version1, version2):
        v1=version1.split(".")
        v2=version2.split(".")
        while v1 or v2:
            x=int(v1.pop(0)) if v1 else 0
            y = int(v2.pop(0)) if v2 else 0

            if x>y:
                return 1
            elif x<y:
                return -1
        return 0

思路二：不使用现成函数，双指针分别指向v1,v2，一次遍历

class Solution(object):
    def compareVersion(self, version1, version2):
        i, j = 0, 0
        l1,l2=len(version1),len(version2)
        while i < l1 or j < l2:
            a = 0
            b = 0
            while i < l1 and version1[i] != '.':#遍历两个点之间的内容
                a = a * 10 + int(version1[i])
                i += 1
            while j < l2 and version2[j] != '.':
                b = b * 10 + int(version2[j])
                j += 1
            i+=1#遇到点要加一，不然就一直在点处循环
            j+=1
            if a > b:
                return 1
            elif a < b:
                return -1
        return 0