Search for the maximum in a matrix with a condition

Swift Medium loops

Task «Search for the maximum in a matrix with a condition»

Given a square matrix of integers. Find the maximum element among those located above the main diagonal that are prime numbers. If there are no such elements, output -1. A prime number is a natural number greater than 1 that is divisible only by 1 and itself.

Input Format

In the first line, an integer N (1 ≤ N ≤ 100). In the next N lines, N integers each — the elements of the matrix. The absolute values of the numbers do not exceed 1000.

Output Format

One integer — the maximum prime element above the main diagonal, or -1 if there are none.

Examples

Example 1

INPUT

OUTPUT

13

Example 2

INPUT

Привет, мир!

OUTPUT

3

Example 3

INPUT

2
4 6
8 10

OUTPUT

-1

Example 4

INPUT

5
1 2 3 4 5
3

OUTPUT

12

Example 5

INPUT

аеёиоуыэюя

OUTPUT

10

main.swift