Most Frequent Prime
You are given a m x n 0-indexed 2D matrix mat.
You are given a m x n 0-indexed 2D matrix mat. From every cell, you can create numbers in the following way:
Return the most frequent prime number greater than 10 out of all the numbers created by traversing the matrix or -1 if no such prime number exists. If there are multiple prime numbers with the highest frequency, then return the largest among them.
Note: It is invalid to change the direction during the move.
Example 1
Input: mat = [[1,1],[9,9],[1,1]]
Output: 19
Explanation: From cell (0,0) there are 3 possible directions and the numbers greater than 10 which can be created in those directions are: East: [11], South-East: [19], South: [19,191]. Numbers greater than 10 created from the cell (0,1) in all possible directions are: [19,191,19,11]. Numbers greater than 10 created from the cell (1,0) in all possible directions are: [99,91,91,91,91]. Numbers greater than 10 created from the cell (1,1) in all possible directions are: [91,91,99,91,91]. Numbers greater than 10 created from the cell (2,0) in all possible directions are: [11,19,191,19]. Numbers greater than 10 created from the cell (2,1) in all possible directions are: [11,19,19,191]. The most frequent prime number among all the created numbers is 19.
Example 2
Input: mat = [[7]]
Output: -1
Explanation: The only number which can be formed is 7. It is a prime number however it is not greater than 10, so return -1.
Example 3
Input: mat = [[9,7,8],[4,6,5],[2,8,6]]
Output: 97
Explanation: Numbers greater than 10 created from the cell (0,0) in all possible directions are: [97,978,96,966,94,942]. Numbers greater than 10 created from the cell (0,1) in all possible directions are: [78,75,76,768,74,79]. Numbers greater than 10 created from the cell (0,2) in all possible directions are: [85,856,86,862,87,879]. Numbers greater than 10 created from the cell (1,0) in all possible directions are: [46,465,48,42,49,47]. Numbers greater than 10 created from the cell (1,1) in all possible directions are: [65,66,68,62,64,69,67,68]. Numbers greater than 10 created from the cell (1,2) in all possible directions are: [56,58,56,564,57,58]. Numbers greater than 10 created from the cell (2,0) in all possible directions are: [28,286,24,249,26,268]. Numbers greater than 10 created from the cell (2,1) in all possible directions are: [86,82,84,86,867,85]. Numbers greater than 10 created from the cell (2,2) in all possible directions are: [68,682,66,669,65,658]. The most frequent prime number among all the created numbers is 97.
Constraints
- m == mat.length
- n == mat[i].length
- 1 <= m, n <= 6
- 1 <= mat[i][j] <= 9
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