So I was at a programming interview a few months ago and this problem tripped me up for some reason. There are a couple of solutions I can think of but most of them seem extremely inefficient. Though I've been programming in some capacity for years, I'm currently in college for a CS degree so my point of reference may be incomplete. I was hoping someone here might offer up some possible solutions:
"Given a set of strings and associated numerical 'values,' assemble a palindrome from these string whose value (defined by the sum of the strings used to create it) is the highest possible."
There were no limits to how many strings could be provided, some strings may not be used.
Example: "asd" - 3 "dsa" - 5 "appa" - 1
Result would be "asdappadsa" with a value of 9.
My thought would be to try all strings in all orders, then drop off one, starting with the lowest valued one, but that solution is O(N!) and I'd assume that's not ok.
(Preferred languages are C and Java, but whatever works)
EDIT: Clarification. Each string provided can only be used once, and has to be used exactly as provided, though you may choose to not use any of the strings in your palindrome. You can not use substrings of provided strings, nor can you reverse the string.