LongestIncreasingSubsequenceDetector v2

LongestIncreasingSubsequenceDetector.java

import java.util.Arrays;

public class LongestIncreasingSubsequenceDetector {
	private int[] 	extractedLongestIncreasingSubsequence;
	private int 	extractedLongestIncreasingSubsequenceLength;
	private int 	extractedLongestIncreasingSubsequenceEndingIndex;
	private int 	extractedLongestIncreasingSubsequenceStartingIndex;

	private int[] optResults;
	private int[] initialNumberSequence;
	
	LongestIncreasingSubsequenceDetector(int[] numberSequence) {
		initialNumberSequence = numberSequence;
		int numberSequenceLength = numberSequence.length;
		optResults = new int[numberSequenceLength]; //any opt can be at minimum 1, initial value of 0 refers to uninitialized cell

		calculateEveryOpt();
		
		int maximumOptIndex 	= getMaximumOptIndex();
		int maximumOptValue 	= optResults[maximumOptIndex];
		
		extractedLongestIncreasingSubsequenceStartingIndex 	= maximumOptIndex;
		extractedLongestIncreasingSubsequenceEndingIndex	= maximumOptIndex + maximumOptValue - 1;
		extractedLongestIncreasingSubsequenceLength 		= maximumOptValue;
		extractedLongestIncreasingSubsequence 				= Arrays.copyOfRange(numberSequence, extractedLongestIncreasingSubsequenceStartingIndex, extractedLongestIncreasingSubsequenceEndingIndex+1);
	}
	public int[] getLongestIncreasingSubsequence() { //Return highest OPT
		return extractedLongestIncreasingSubsequence;
	}
	public int getLongestIncreasingSubsequenceLength() {
		return extractedLongestIncreasingSubsequenceLength;
	}
	public int getLongestIncreasingSubsequenceEndingIndex() {
		return extractedLongestIncreasingSubsequenceEndingIndex;
	}
	public int getLongestIncreasingSubsequenceStartingIndex() {
		return extractedLongestIncreasingSubsequenceStartingIndex;
	}
	public int[] getOptValues() {
		return optResults;
	}
	public int longestIncreasingSubsequenceLengthThatStartsFromIndex(int startingIndex) {
		return OPT(startingIndex, initialNumberSequence);
	}
	private void calculateEveryOpt() {
		for(int i=0; i<initialNumberSequence.length;i++) {
			int length = this.longestIncreasingSubsequenceLengthThatStartsFromIndex(i);
			System.out.println("Longest subsequence's length that exactly starts at index "+i+" is "+length);
		}
	}
	private int getMaximumOptIndex() {
		int maxLength 	= 0;
		int maxIndex 	= 0;
		for(int i=0; i<optResults.length; i++) {
			if(optResults[i] > maxLength) {
				maxLength 	= optResults[i];
				maxIndex 	= i;
			}
		}
		return maxIndex;
	}
	private int OPT(int j, int[] numberSequence) { //longest increasing sub sequence that exactly starts from j
		if(j == numberSequence.length-1) { //Special case: Last number's length at the sequence, is one. We already know it.
			if(optResults[j]==0) {
				System.out.println("OPT("+j+"): MISS");
				optResults[j] = 1;
			} else {
				System.out.println("OPT("+j+"): HIT");
			}
			return optResults[j];
		} else {
			boolean isNextNumberSmaller = (numberSequence[j+1] <= numberSequence[j]);
			if(isNextNumberSmaller) { //Then, this is subsequence with length 1
				if(optResults[j]==0) {
					System.out.println("OPT("+j+"): MISS");
					optResults[j] = 1;
				} else {
					System.out.println("OPT("+j+"): HIT");
				}
				return optResults[j];
			} else {
				if(optResults[j]==0) {
					System.out.println("OPT("+j+"): MISS");
					optResults[j] = 1 + OPT(j+1, numberSequence);
				} else {
					System.out.println("OPT("+j+"): HIT");
				}
				return 1+optResults[j+1];
			}
		}
	}
}

Main.java

import java.util.Arrays;

public class Main {
	public static void main(String[] args) {
		int[] numberSequence = new int[]{1,2,3,1,2,3};
		LongestIncreasingSubsequenceDetector LISD = new LongestIncreasingSubsequenceDetector(numberSequence);
		
		System.out.println("\n --RESULTS--");
		System.out.println("Input number sequence: "+Arrays.toString(numberSequence));
		System.out.println("");
		System.out.println("Longest subsequence starting index: "+LISD.getLongestIncreasingSubsequenceStartingIndex());
		System.out.println("Longest subsequence length: "+LISD.getLongestIncreasingSubsequenceLength());
		System.out.println("Longest number sequence: "+Arrays.toString(LISD.getLongestIncreasingSubsequence()));
		System.out.println("");
		System.out.println("OPT Values: "+Arrays.toString(LISD.getOptValues()));
	}
}