Description for this problem is really long. In short -
Given the set of keys on a keypad, a set of letters to assign on those keys sequentially and each letters' frequency on a dictionary, you have to design an optimal keypad layout (assign letters to keys) such that overall typing price is lowest. The price is determined as the sum of the prices of each letter. The price of a letter is a product of the letter frequency (Fi) and its position on the key.
