find maximum value recursively with a List

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This method I'm trying to write finds the maximum value of integers in a list, and for the assignment I have to use recursion. I think I understand the concept of recursion, but doing it with Lists or arrays is something I don't understand. Does it always require splitting the List or array in half? Anyways, this code will compile, but I'm getting an IndexOutOfBounds error in a line I've commented below. Does it look remotely close to what I should be doing?

public static final int findMaxRecursively(List<Integer> numbers) {
int max = 0;

     if(numbers.size() == 1)
       return numbers.size();

     List<Integer> bottomHalf = new ArrayList<Integer>(numbers.size()/2);
     for (int i= 0; i<numbers.size()/2;i++){
         if (bottomHalf.get(i) > max) // here's where the IndexOutOfBounds error occurs
          max = bottomHalf.get(i);
          }
          findMaxRecursively(bottomHalf);

     List<Integer> topHalf = new ArrayList<Integer>(numbers.size()/2);
     for(int i = numbers.size()/2; i< numbers.size(); i++){
         if (topHalf.get(i) > max)   
         max = topHalf.get(i);
    }
         findMaxRecursively(topHalf);

         return max;
}

asked 20 secs ago

silentkit

7

find maximum value recursively with a List