【LeetCode】165 - 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

Solution：类似于split的方法把字符串解析, 遇到'.'就判断之前的sum1和sum2

 class Solution {
 public:
     int compareVersion(string version1, string version2) {
         int sum1=,sum2=;
         int n1=version1.size(),n2=version2.size();
         for(int i=,j=;i<n1||j<n2;i++,j++){
             while(i<n1&&version1[i]!='.'){
                 sum1=sum1*+version1[i]-'';
                 i++;
             }
             while(j<n2&&version2[j]!='.'){
                 sum2=sum2*+version2[j]-'';
                 j++;
             }
             if(sum1>sum2)return ;
             else if(sum1<sum2)return -;
             else{
                 sum1=;
                 sum2=;
             }
         }
         return ;
     }
 };