Given an array of strings words, return true if it forms a valid word square.

A sequence of strings forms a valid word square if the k^th row and column read the same string, where 0 <= k < max(numRows, numColumns).

Example 1:

Input: words = ["abcd","bnrt","crmy","dtye"]
Output: true
Explanation:
The 1^st row and 1^st column both read "abcd".
The 2^nd row and 2^nd column both read "bnrt".
The 3^rd row and 3^rd column both read "crmy".
The 4^th row and 4^th column both read "dtye".
Therefore, it is a valid word square.

Example 2:

Input: words = ["abcd","bnrt","crm","dt"]
Output: true
Explanation:
The 1^st row and 1^st column both read "abcd".
The 2^nd row and 2^nd column both read "bnrt".
The 3^rd row and 3^rd column both read "crm".
The 4^th row and 4^th column both read "dt".
Therefore, it is a valid word square.

Example 3:

Input: words = ["ball","area","read","lady"]
Output: false
Explanation:
The 3^rd row reads "read" while the 3^rd column reads "lead".
Therefore, it is NOT a valid word square.

Constraints:

1 <= words.length <= 500
1 <= words[i].length <= 500
words[i] consists of only lowercase English letters.

Valid Word Square

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