ElectoralCounts.java

import java.util.Arrays;
import java.util.Vector;

public class ElectoralCounts {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		int[] votes = { 9, 3, 11, 6, 55, 9, 7, 3, 3, 29, 16, 4, 4, 20, 11, 6,
				6, 8, 8, 4, 10, 11, 16, 10, 6, 10, 3, 5, 6, 4, 14, 5, 29, 15,
				3, 18, 7, 7, 20, 4, 9, 3, 11, 38, 6, 3, 13, 12, 5, 10, 3 };
		int sum = 0;
		for (int i = 0; i < votes.length; i++) {
			sum += votes[i];
		}
		calculateMaxSum(votes, sum / 2);
	}

	public static void calculateMaxSum(int[] votes, int sum) {
		int[][] M = new int[votes.length + 1][sum + 1];
		numSolutions = new long[votes.length + 1][sum + 1];
		resetNumSolutions();
		for (int i = 1; i <= votes.length; i++) {
			int w_i = votes[i - 1];
			for (int w = 0; w <= sum; w++) {
				if (w < w_i) {
					M[i][w] = M[i - 1][w];
				} else {
					int choiceAddElement = votes[i - 1] + M[i - 1][w - w_i];
					int choiceIgnoreElement = M[i - 1][w];
					if (choiceAddElement > choiceIgnoreElement) {
						M[i][w] = choiceAddElement;
					} else {
						M[i][w] = choiceIgnoreElement;
					}
				}
			}
		}

		// M[votes.length][sum] = 269
		PathCount(M, votes, votes.length, sum);

		System.out.println(M[votes.length][sum]);
		System.out.println("Num Solutions: " + numSolutions[votes.length][sum]);
		System.out.println(bad_items);

		// printOptArray(M);
		// printNumSolutionsArray();
	}

	private static long path_count = 0;
	private static long bad_items = 0;
	private static Vector<Integer> soln = new Vector<Integer>();

	private static long[][] numSolutions;
	
	public static long PathCount(int[][] M, int[] votes, int i, int j) {
		if (i < 0 || j < 0) {
			bad_items++;
			return 0;
		}

		if (numSolutions[i][j] != -1)
		{
			return numSolutions[i][j];
		}
		if (i == 0 && j == 0) {
			// printOutSolution();
			path_count++;
			return 1;
		} else {
			int w = j;
			int w_i = votes[i - 1];

			if (w < w_i) {
				M[i][w] = M[i - 1][w];
				numSolutions[i][j] = PathCount(M, votes, i - 1, w);
			} else {
				int choiceAddElement = votes[i - 1] + M[i - 1][w - w_i];
				int choiceIgnoreElement = M[i - 1][w];
				if (choiceAddElement == choiceIgnoreElement) {
					numSolutions[i][j] = PathCount(M, votes, i - 1, w);
					soln.add(w_i);
					numSolutions[i][j] += PathCount(M, votes, i - 1, w - w_i);
					soln.removeElement(w_i);

				} else {
					if (choiceAddElement > choiceIgnoreElement) {
						M[i][w] = choiceAddElement;
						soln.add(w_i);
						numSolutions[i][j] = PathCount(M, votes, i - 1, w - w_i);
						soln.removeElement(w_i);
					} else {
						M[i][w] = choiceIgnoreElement;
						numSolutions[i][j] = PathCount(M, votes, i - 1, w);
					}
				}
			}
			return numSolutions[i][j];
		}
	}

	private static void printOutSolution() {
		int sum = 0;
		for (int k = 0; k < soln.size(); k++) {
			sum += soln.elementAt(k);
		}
		Object[] solnArray = soln.toArray();
		// Arrays.sort(solnArray);
		System.out.println(sum + ": " + Arrays.toString(solnArray));
		// soln.clear();
	}

	private static void printOptArray(int[][] M) {
		for (int i = 0; i < M.length; i++) {
			System.out.println("");
			for (int j = 0; j < M[i].length; j++) {
				System.out.print(M[i][j] + " ");
			}
		}
	}

	private static void printNumSolutionsArray() {
		for (int i = 0; i < numSolutions.length; i++) {
			System.out.println("");
			for (int j = 0; j < numSolutions[i].length; j++) {
				System.out.print(numSolutions[i][j] + " ");
			}
		}
	}
	
	private static void resetNumSolutions() {
		for (int i = 0; i < numSolutions.length; i++) {
			for (int j = 0; j < numSolutions[i].length; j++) {
				numSolutions[i][j] = -1;
			}
		}
	}
}