# 165. Compare Version Numbers

#### Medium

***

Given two version numbers, `version1` and `version2`, compare them.

*

Version numbers consist of **one or more revisions** joined by a dot `'.'`. Each revision consists of **digits** and may contain leading **zeros**. Every revision contains **at least one character**. Revisions are **0-indexed from left to right**, with the leftmost revision being revision 0, the next revision being revision 1, and so on. For example `2.5.33` and `0.1` are valid version numbers.

To compare version numbers, compare their revisions in **left-to-right order**. Revisions are compared using their **integer value ignoring any leading zeros**. This means that revisions `1` and `001` are considered **equal**. If a version number does not specify a revision at an index, then **treat the revision as `0`**. For example, version `1.0` is less than version `1.1` because their revision 0s are the same, but their revision 1s are `0` and `1` respectively, and `0 < 1`.

*Return the following:*

* If `version1 < version2`, return `-1`.
* If `version1 > version2`, return `1`.
* Otherwise, return `0`.

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**Example 1:**

```
Input: version1 = "1.01", version2 = "1.001"
Output: 0
Explanation: Ignoring leading zeroes, both "01" and "001" represent the same integer "1".
```

**Example 2:**

```
Input: version1 = "1.0", version2 = "1.0.0"
Output: 0
Explanation: version1 does not specify revision 2, which means it is treated as "0".
```

**Example 3:**

```
Input: version1 = "0.1", version2 = "1.1"
Output: -1
Explanation: version1's revision 0 is "0", while version2's revision 0 is "1". 0 < 1, so version1 < version2.
```

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**Constraints:**

* `1 <= version1.length, version2.length <= 500`
* `version1` and `version2` only contain digits and `'.'`.
* `version1` and `version2` **are valid version numbers**.
* All the given revisions in `version1` and `version2` can be stored in a **32-bit integer**.

```python
class Solution:
    def compareVersion(self, version1: str, version2: str) -> int:
        result = 0
        arr1 = version1.split('.')
        arr2 = version2.split('.')
        length = min(len(arr1), len(arr2))
        index = 0
        while index < length:
            if int(arr1[index]) < int(arr2[index]):
                return -1
            elif int(arr1[index]) > int(arr2[index]):
                return 1
            index += 1
        index1 = index
        index2 = index
        while index1 < len(arr1):
            if int(arr1[index1]) != 0:
                return 1
            index1 += 1
        while index2 < len(arr2):
            if int(arr2[index2]) != 0:
                return -1 
            index2 += 1
        return result
```