There is a 8∗8 board and the numbers 1,2,3,4,...,63,64. In all the unit squares of the board, these numbers are places such that only 1 numbers goes to only one unit square. Prove that there is atleast 4 2∗2 squares such that the sum of the numbers in 2∗2 is greater than 100. combinatoricsJuniorAzerbaijanBound