Several microorganisms of different families have been arranged next to each other. Knowing that a microorganism eats its neighbor if it is of a different family and smaller in size, write a program that returns the largest family and its size when the situation reaches an equilibrium.

microorganisms.java

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

/**
 * Several microorganisms of different families have been arranged next to each other. Knowing that a microorganism eats its neighbor if it is of a different family and smaller in size, write a program that returns the largest family and its size when the situation reaches an equilibrium.
 *
 * <ul>
 *     Process:
 *     <li>Each microorganism belongs to a family, defined by a letter, and has a size, defined by an integer.</li>
 *     <li>At each simulation round, a microorganism can eat a neighbor (directly to the left or to the right) if the latter is from another family and has a stricly smaller size. If there is a target on both sides, the left one is chosen.</li>
 *     <li>During a round, the resolution is done from left to right. For example, if a microorganism can be eaten by both its left and right neighbors, the left one is chosen.</li>
 *     <li>When a microorganism eats another, its size increases by the size of its target and the place occupied by the target disappears</li>
 *     <li>In the same simulation round, a microorganism cannot both eat and eaten. The choice of event (eating or being eaten) is determined by the order of resolution.</li>
 *     <li>The simulation ends when no more microorganisms can eat others.</li>
 * </ul>
 * <p>
 * At the end of the simulation, take the microorganism with the target size, return a string consisting of its family, a separation space and its size.
 */
public class CodingGame {
    public static void main(String[] args) {
        // Names of the bacteria families.
        List<String> families = new ArrayList<>(Arrays.asList("A", "B", "C", "B", "B", "A", "C"));
        // Sizes of the bacteria families.
        List<Integer> sizes = new ArrayList<>(Arrays.asList(5, 5, 2, 10, 4, 6, 7));

        int idx = 1;
        String lastFamily = null;
        while (sizes.size() > 1) {
            if (idx + 1 < sizes.size() && families.get(idx).equals(lastFamily)) {
                idx++;
                continue;
            }

            if (sizes.get(idx - 1) > sizes.get(idx)) {
                lastFamily = families.get(idx - 1);

                // Update
                sizes.set(idx - 1, sizes.get(idx - 1) + sizes.get(idx));

                // Remove bacteria
                sizes.remove(idx);
                families.remove(idx);
            } else if (sizes.get(idx) > sizes.get(idx - 1)) {
                lastFamily = families.get(idx);

                // Update
                sizes.set(idx, sizes.get(idx - 1) + sizes.get(idx));

                // Remove bacteria
                sizes.remove(idx - 1);
                families.remove(idx - 1);
            }

            // Go forward or backward
            if (idx + 1 >= sizes.size()) {
                idx--;
            } else {
                idx++;
            }
        }

        // Name and size of the biggest bacteria family.
        System.out.printf("WIN: %s %d%n", families.get(0), sizes.get(0));
    }
}