How to find the minimum value in an ArrayList, along with the index number? (Java)

Question

I need to get the index value of the minimum value in my arraylist in Java. MY arraylist holds several floats, and I\'m trying to think of a way I can get the index number o

Answer 1

You can use Collections.min and List.indexOf:

int minIndex = list.indexOf(Collections.min(list));

If you want to traverse the list only once (the above may traverse it twice):

public static > int findMinIndex(final List xs) {
    int minIndex;
    if (xs.isEmpty()) {
        minIndex = -1;
    } else {
        final ListIterator itr = xs.listIterator();
        T min = itr.next(); // first element as the current minimum
        minIndex = itr.previousIndex();
        while (itr.hasNext()) {
            final T curr = itr.next();
            if (curr.compareTo(min) < 0) {
                min = curr;
                minIndex = itr.previousIndex();
            }
        }
    }
    return minIndex;
}