Genetic Algorithm

package javaapplication1;

import java.util.Arrays;

public class JavaApplication1 {

    static int fitness[] = new int[4];
    static int pop[] = new int[4];
    static double probabilities[] = new double[4];
    static double expectedCount[] = new double[4];
    static int actualCount[] = new int[4];
    static String binary[] = new String[4];

    static void calculateProbability() {
        int sum = 0;
        for (int i = 0; i < fitness.length; i++) {

            sum += fitness[i];
        }
        for (int i = 0; i < fitness.length; i++) {

            probabilities[i] = fitness[i] / sum;
            expectedCount[i] = probabilities[i]*4;
            actualCount[i] = (int)Math.round(expectedCount[i]);
        }
    }

    static void populationGenerator() {
        for (int i = 0; i < pop.length; i++) {
            pop[i] = (int) (Math.random() * 100) % 31;

            String s = Long.toBinaryString(pop[i]);
            while (s.length() < 5) {
                s = "0" + s;
            }
            binary[i] = s;
            fitness[i] = pop[i] * pop[i];
        }
        System.out.println(binary[3]);
        calculateProbability();
    }

    public static void main(String[] args) {
        // TODO code application logic here
        populationGenerator();
        for(int i = 0 ; i < 4 ; i ++ ) {

        System.out.println(binary[i]+"  "+fitness[i]+"  "+probabilities[i]+"  "+expectedCount[i]+"  "+actualCount[i]);
        }
    }
}