# $10\times10$ table of numbers with differences of adjacent entries no more than 5

In each square in a table $10\times 10$ we write a whole number so the difference between any two numbers by the neighboring squares must be no more than $5$ (two squares are neighboring if they have a common side). Show that two of the numbers must be equal. Please help me!

-
What have you tried? – Matt Pressland Feb 28 at 18:33

 Please give me a complete demonstration. – Manuel Feb 28 at 21:08 Done. ${}{}{}{}{}{}{}$ – Joe Z. Feb 28 at 21:21 Well done, Joe --- now Manuel can just hand this in as his own work, without putting even a smidgen of effort into it, or having learned anything at all from it. He'll be back for more. – Gerry Myerson Feb 28 at 21:44 I was simply assuming good faith. He had two hours to do it himself. – Joe Z. Mar 1 at 0:06