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

Runtime: 0ms

1 class Solution { 2 public: 3     int compareVersion(string version1, string version2) { 4         int m = version1.size(), n = version2.size(); 5         int i = 0, j = 0; 6          7         while(i < m || j < n){ 8             int temp1 = 0, temp2 = 0; 9             while(i < m && version1[i] != '.'){10                 temp1 = temp1 * 10 + version1[i] - '0';11                 i++;12             }13             while(j < n && version2[j] != '.'){14                 temp2 = temp2 * 10 + version2[j] - '0';15                 j++;16             }17             if(temp1 > temp2) return 1;18             if(temp1 < temp2) return -1;19             i++;20             j++;21         }22         return 0;23     }24 };