python3

javascript

java

Longest Common Prefix

Write a function to find the longest common prefix string amongst an array of strings `strs` of size `n`.

If there is no common prefix, return a string `"null"`.

### Input Format
First Parameter: Number`n`

Second Parameter: An array of strings `strs` of size `n`

### Output Format
Return a string

### Example 1
```
Input: 
3
flower flow flight
Output: 
fl
```

### Example 2
```
Input: 
3
dog racecar car
Output: 
null
Explanation: There is no common prefix among the input strings.
```

#### Constraints
- `1 <= n <= 200`
- `0 <= strs[i].length <= 200` 
- `strs[i]` consists of only lowercase English letters.
- **Expected Time Complexity** - `O(n*m)` where `m` is the length of the `ans`
- **Expected Space Complexity** - `O(1)`

string solve(int n, vector<string> strs){
//CODE HERE 
}

static String solve(int n, String[] strs){
//CODE HERE 
}