MaxSequenceSum.java

/**
 * @author Harshith Iyer (@harbar20)
 * @author Luke Carapezza (@lukec11)
 * @ver 0.1
 */

import java.util.Arrays;
import java.util.Random;

class MaxSequenceSum {
	public static int sum(int[] ints) {
		int sum = 0;
		for (int num : ints)
			sum += num;
		
		return sum;
	}
  
  /**
  * @param int[] ints - An unsorted array of integers
  * The time complexity of this algorithm is O(4n^2)
  * @return highest sum of a subsequence of the array
  */
	public static int maxSequenceSum(int[] ints) {
		int max = 0;
		for (int i = 0; i < ints.length; i++) {
			for (int j = 0; j < i; j++) {
				int[] subarray = Arrays.copyOfRange(ints, j, i);
				int sum = sum(subarray);
				if (sum > max) {
					max = sum;
				}
			}
		}
		return max;
	}

  /**
   * @param int size - the size of the reqested random int array
   * @return an array of $size random ints
   * generates and returns an array of $size random integers
   */                 
	public static int[] getRandomNumbers(int size) {
		Random random = new Random();
		int[] randomNums = new int[20];                                        
		for (int i = 0; i < 20; i++) {       
			randomNums[i] = random.nextInt(20) -10;
		}          

		System.out.print("Array: ");
		
		for (int i = 0; i < randomNums.length; i++) {
			System.out.print(randomNums[i] + " | ");
		}

    return randomNums;
	}


	public static void main(final String[] args) {
		final int[] ints = getRandomNumbers(20);
		final int MAXSUM = maxSequenceSum(ints);
		System.out.println("\nMax sum is: " + MAXSUM);
	}
}