baobab's blog

By baobab, history, 5 years ago, In English

Link to problem statement

Let's first fill up the sack with as small items as possible, until we can't fill it anymore. The difference between current weight and max weight can be at most 8 (with the exception of trivial inputs) and there are only 8 distinctive items. So if we need to create a sequence of actions which takes us from the current weight to the optimal weight, we don't need many actions to do that. Now, here comes the funny part: instead of constructing a short, smart sequence of actions, we can simply construct a long, dumb sequence of actions. If we choose every action in a greedy, randomized way, we will probably visit the optimal weight at some point in the sequence. What do I mean by greedy? If we are under max weight, let's add a random item to the sack. If we are over max weight, let's remove a random item from the sack. That's it!

There's still time to hack my solution. Have fun!

  • Vote: I like it
  • +44
  • Vote: I do not like it

»
5 years ago, # |
  Vote: I like it -14 Vote: I do not like it

Why bother with clever ideas or even random if you can go through all the cases (2^8=256) and find the best result via the dumbest way possible?

  • »
    »
    5 years ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    How? There's more than 256 cases.

    • »
      »
      »
      5 years ago, # ^ |
      Rev. 3   Vote: I like it -13 Vote: I do not like it

      There are 8 items to choose from You can either choose an item or leave it – two states So it is 2^8, isn't it?

      Edit: my bad, this solution won't work

      • »
        »
        »
        »
        5 years ago, # ^ |
          Vote: I like it +1 Vote: I do not like it

        No, there can be any amount of any item.

      • »
        »
        »
        »
        5 years ago, # ^ |
          Vote: I like it 0 Vote: I do not like it

        There's 8 different kinds of items. Each item has a weight from 1 to 8 (inclusive). You have up to 10^16 of each item.

»
5 years ago, # |
  Vote: I like it +1 Vote: I do not like it

I just confirmed this solution runs !

This is geniosity max.