How to Compare Version Numbers in Java

The challenge

Compare two version numbers version1 and version2.
If <em>version1</em>&nbsp;>&nbsp;<em>version2</em> return 1; if <em>version1</em>&nbsp;<&nbsp;<em>version2</em> return -1;otherwise return ``.

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.

You may assume the default revision number for each level of a version number to be . For example, version number `3.4` has a revision number of `3` and `4` for its first and second level revision number. Its third and fourth level revision number are both .

Example 1:

Input: version1 = "0.1", version2 = "1.1"
Output: -1

Example 2:

Input: version1 = "1.0.1", version2 = "1"
Output: 1

Example 3:

Input: version1 = "7.5.2.4", version2 = "7.5.3"
Output: -1

Example 4:

Input: version1 = "1.01", version2 = "1.001"
Output: 0
Explanation: Ignoring leading zeroes, both “01” and “001" represent the same number “1”

Example 5:

Input: version1 = "1.0", version2 = "1.0.0"
Output: 0
Explanation: The first version number does not have a third level revision number, which means its third level revision number is default to "0"

Note:

1. Version strings are composed of numeric strings separated by dots . and this numeric strings may have leading zeroes.
2. Version strings do not start or end with dots, and they will not be two consecutive dots.

The solution in Java

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class Solution {
    public int compareVersion(String version1, String version2) {
        
        String[] arr1 = version1.split("\\.");
        String[] arr2 = version2.split("\\.");

        int i=0;
        while(i<arr1.length || i<arr2.length){
            if(i<arr1.length && i<arr2.length){
                if(Integer.parseInt(arr1[i]) < Integer.parseInt(arr2[i])) return -1;
                else if(Integer.parseInt(arr1[i]) > Integer.parseInt(arr2[i])) return 1;
            } else if(i<arr1.length){
                if(Integer.parseInt(arr1[i]) != 0) return 1;
            } else if(i<arr2.length){
               if(Integer.parseInt(arr2[i]) != 0) return -1;
            }

            i++;
        }

        return 0;
        
    }
}