2133. Check if Every Row and Column Contains All Numbers
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An n x n matrix is valid if every row and every column contains all the integers from 1 to n (inclusive).
Given an n x n integer matrix matrix, return true if the matrix is valid. Otherwise, return false.
Example 1:
Input: matrix = [[1,2,3],[3,1,2],[2,3,1]] Output: true Explanation: In this case, n = 3, and every row and column contains the numbers 1, 2, and 3. Hence, we return true.
Example 2:
Input: matrix = [[1,1,1],[1,2,3],[1,2,3]] Output: false Explanation: In this case, n = 3, but the first row and the first column do not contain the numbers 2 or 3. Hence, we return false.
Constraints:
n == matrix.length == matrix[i].length1 <= n <= 1001 <= matrix[i][j] <= n
Hints
Hint 1
Use for loops to check each row for every number from 1 to n. Similarly, do the same for each column.
Hint 2
For each check, you can keep a set of the unique elements in the checked row/col. By the end of the check, the size of the set should be n.