Compare two version numbers version1 and version1.

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

本题特殊情况要考虑到。v1 和v1.0 的比较。

public class Solution {

    public int compareVersion(String version1, String version2) {

        String[] splits1=version1.split("\\.",-1);

        String[] splits2=version2.split("\\.",-1);

        int shortLength=Math.min(splits1.length,splits2.length);

        int longLength=Math.max(splits2.length,splits1.length);

        int i=0;

        for(i=0;i<shortLength;i++)

        {

            if(Integer.parseInt(splits1[i])<Integer.parseInt(splits2[i]))

            {

                return -1;

            }

            else if(Integer.parseInt(splits1[i])>Integer.parseInt(splits2[i]))

            {

                return 1;

            }

        }

        if(i==longLength)

        {

            return 0;

        }

        else

        {

            while(i<longLength)//如果两个版本号不同长度，但是是同一版本的情况，如v1.0 和v1

            {

                if(splits1.length==longLength)

                {

                    if(Integer.parseInt(splits1[i])!=0)

                    {

                        return 1;

                    }

                }

                else if(splits2.length==longLength)

                {

                    if(Integer.parseInt(splits2[i])!=0)

                    {

                        return -1;

                    }

                }

                i++;

            }

            return 0;

        }

    }

}