The Big Programming Thread - Page 335

import java.util.Arrays;


public class HillClimbing {

	public static int[] literals = new int[8];
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		// randomize(literals); // Randomize initial state.
		
		boolean[] startingState = new boolean[8];
		boolean[] leftNeighbor;
		boolean[] rightNeighbor;
		int Number = 0;
		int numOfSatClause = 0;
		Number = generateRandomStart(startingState);
		while(numOfSatClause < 10){
			
	    leftNeighbor = generateNeighbor(Number-1);
	    rightNeighbor = generateNeighbor(Number+1);
	    if (checkSat(startingState) < checkSat(leftNeighbor)){
	    	numOfSatClause = checkSat(leftNeighbor);
	    	startingState = leftNeighbor;
	    	Number--;
	    	System.out.println("Changing starting state");
	    	}
	    else {
	    	numOfSatClause = checkSat(rightNeighbor);
	    	startingState = rightNeighbor;
	    	System.out.println("Changing starting state");
	    	Number++;
	    	}
		}
		System.out.println("Number of true clauses: " + numOfSatClause);
		System.out.println(Number + " = " + Arrays.toString(startingState));
		

	}
	
	private static int checkSat(boolean[] state) {
		int ctr = 0;
		if(!state[7] || !state[5] || !state[4] || state[3]) // ~A V ~C V ~D V E
			ctr++;
		if(!state[7] || !state[6] || !state[4] || !state[0]) // ~A V ~B V ~D V ~H 
			ctr++;
		if(state[6] || state[4] || !state[2] || !state[0]) // B V D V ~F V ~H 
			ctr++;
		if(state[6] || !state[5] || state[1] || !state[0]) // B V ~C V G V ~H 
			ctr++;
		if(!state[6] || state[5] || !state[2] || !state[1]) // ~B V C V ~F V ~G
			ctr++;
		if(state[5] || !state[4] || state[3] || !state[0]) // C V ~D V E V ~H
			ctr++;
		if(!state[5] || state[4] || !state[3] || !state[2]) // ~C V D V ~E V ~F
			ctr++;
		if(state[6] || !state[4] || !state[2] || state[0]) // B V ~D V ~F V H
			ctr++;
		if(!state[7] || !state[5] || !state[4] || state[3]) // ~A V ~C V ~D V E
			ctr++;
		if(state[6] || state[5] || !state[4] || !state[2]) // B V C V ~D V ~F
			ctr++;
		return ctr;
	}

	private static boolean[] generateNeighbor(int randomNumber) {
		boolean[] neighbor = new boolean[8];
		
		for (int i = 7; i >= 0; i--) {
	    	neighbor[i] = (randomNumber & (1 << i)) != 0;
	    }
	    
	    System.out.println(randomNumber + " = " + Arrays.toString(neighbor));
	    return neighbor;
	}
	
	private static int generateRandomStart(boolean[] startingState) {
		int input = (int) (Math.random()*(128));
    
	    for (int i = 6; i >= 0; i--) {
	    	startingState[i] = (input & (1 << i)) != 0;
	    }

	    System.out.println(input + " = " + Arrays.toString(startingState));
	    return input;
	}
}