# Problem 11 Largest product in a grid

In the $20×20$ grid below, four numbers along a diagonal line have been marked in red.

The product of these numbers is $26 × 63 × 78 × 14 = 1788696$.
What is the greatest product of four adjacent numbers in the same direction (up, down, left, right, or diagonally) in the $20×20$ grid?

# 代码实现

Thank you for your support to Jason ~