Connected Flower Field

Problem Statement

Connected Flower Field Problem Description Bob is a florist. His field is a grid of m rows and n columns of cells, and every cell holds exactly one flower. The integer written in a cell is the identifier of the flower type growing there: two cells hold the same type of flower exactly when they hold the same integer. Bob has received an order for a large bouquet, and the customer will accept at most two different types of flower in it. Bob is in a hurry, so he will not walk all over the field: he will pick from a single area of the field. An area is a set of cells such that the cells of the area use at most two distinct flower types in total, and the area is connected - starting from any cell of the area you can reach any other cell of the area by repeatedly stepping to a cell of the area that shares a side with the current one. Write a program that finds the largest such area and prints how many cells it contains. Read the input from STDIN and print the output to STDOUT. Do not print a