A Basic Seaborn Heatmap

Brindle & Co measures footfall in every aisle of a store, hour by hour, and hands the result over as a grid: one line per aisle, one number per hour. The shift planner colours that grid so the busy corners stand out, but the staffing rule is written against a single number -- the busiest cell anywhere in the grid, whichever aisle and hour it belongs to.

Task: Print the largest value in the grid.

Input

The first line holds two integers separated by a single space: how many rows the grid has, then how many columns, each between 1 and 100. Then come that many rows, each holding that many numbers separated by single spaces. Values may be negative.

Output

One line holding the largest value in the whole grid, rounded to 2 decimal places. Largest means highest, not furthest from zero: with every value negative, the answer is the one closest to zero.

Example:

Input:
2 2
1 5
8 3

Output:
8.00