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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

2. Analysis

3. Solution(s)

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public int (String version1, String version2) {
		String[] v1 = version1.split("\."); 
		String[] v2 = version2.split("\.");
		int len = Integer.min(v1.length, v2.length);
		for(int i=0; i<len; i++){
			if(Integer.valueOf(v1[i]) > Integer.valueOf(v2[i]))
				return 1;
			else if(Integer.valueOf(v1[i]) < Integer.valueOf(v2[i]))
				return -1;
		}
		if(v1.length > v2.length && Integer.valueOf(v1[v1.length-1]) != 0) // compare 1.0 and 1
			return 1;
		else if(v1.length < v2.length && Integer.valueOf(v2[v2.length-1]) != 0)
			return -1;
		else
			return 0;
}