【Leetcode】【Easy】Compare Version Numbers

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.

Here is an example of version numbers ordering:

0.1 < 1.1 < 1.2 < 13.37

解题：

题目的意思是，比较版本号的大小，2版本比1版本大，而2.10版本比2.5版本大；

分别取出小数点前和小数点后的数字做比较；

代码：

 class Solution {
 public:
     int compareVersion(string version1, string version2) {
         int len1 = version1.size();
         int len2 = version2.size();
         int num1 = ;
         int num2 = ;
         int i = ;
         int j = ;
         while(i < len1 || j < len2) {
             while (i < len1 && version1[i] != '.') {
                 num1 = num1 *  + (version1[i] - '');
                 i++;
             }

             while (j < len2 && version2[j] != '.') {
                 num2 = num2 *  + (version2[j] - '');
                 j++;
             }

             if(num1 > num2)
                 return ;
             else if (num1 < num2)
                 return -;

             num1 = ;
             num2 = ;
             i++;
             j++;
         }

         return ;
     }
 };