This one is very simple. A 20 x 20 grid contains a bunch of 5-7 digit numbers in any of eight orientations. I.e. along diagonals, horizontally and vertically and forward or backward. The numbers are in a line and fit completely in the grid and don't overlap, or share digits.
Can your code find all the numbers faster than anyone else's? It's a month early, and Challenge 58 is due to start in a few days on May 1st.