import java.util.*;

public class C {
    public String makeString() {
        String initialString = "Hello";
        String result = "";
        for(int i=0; i < initialString.length(); i++) {
            result = result + initialString.charAt(i) + "-";
        }
        return result;

    }

    public ArrayList<String> getWords(String string) {
        ArrayList<String> result = new ArrayList<String>();

        String currentWord = "";

        for(int i=0; i < string.length(); i++) {
            char c = string.charAt(i);
            if (c == ' ') {
                result.add(currentWord);
                currentWord = "";
            } else {
                currentWord += c;
            }
        }

        if (currentWord.length() > 0) {
            result.add(currentWord);
        }

        return result;
    }

    public ArrayList<String> removeDuplicates(ArrayList<String> list) {
        ArrayList<String> result = new ArrayList<String>();

        for(String string: list) {
            if (!result.contains(string)) {
                result.add(string);
            }
        }

        return result;
    }

    public ArrayList<String> setIntersection(ArrayList<String> a, ArrayList<String> b) {
        // a and b have duplicates alread removed
        ArrayList<String> result = new ArrayList<String>();

        if (a == null || b == null || a.size() == 0 || b.size() == 0) { return result; }

        for(String string: a) {
            if (b.contains(string)) {
                result.add(string);
            }
        }

        return result;
    }

    public ArrayList<String> setUnion(ArrayList<String> a, ArrayList<String> b) {
        ArrayList<String> result = new ArrayList<String>();

        for(String word: a) {
            result.add(word);
        }

        for(String word: b) {
            result.add(word);
        }

        result = removeDuplicates(result);
        return result;
    }


    public double jaccard(String first, String second) throws Exception {
        // return the result of the intersection over the union
        if (first == null || second == null) {
            throw new Exception("Dont use nulls!");
        }

        if (first.equals(second)) {
            return 1.0;
        }

        ArrayList<String> fa = removeDuplicates(getWords(first.toLowerCase()));
        ArrayList<String> sa = removeDuplicates(getWords(second.toLowerCase()));

        double numerator = (double)setIntersection(fa, sa).size();
        if (numerator == 0.0) {
            return 0.0;
        }
        double denominator = (double)setUnion(fa, sa).size();
        if (denominator == 0.0) {
            return 0.0;
        }

        return (numerator / denominator);
    }

    public void someMethod(int val) {
        if (val == 0) {
            return;
        }

        System.out.println("val is not zero");

    }

    public static void main(String args[]) {
        C c = new C();
        c.someMethod(10);

        //double jaccardValue  = -1.0;
        //try {
            //jaccardValue = c.jaccard(null, null);
        //} catch (Exception ex) {
            //System.out.println(ex.getMessage());
        //}

        //ArrayList<String> val = c.getWords("hello world again something stuff more last ");
        //int expected = 7;
        //int result = val.size();
        //if (expected != result) {
            //System.out.println("Expected is not equal to the result");
            //System.out.println("Expected: " + expected + ", result: " + result);
        //}
        //System.out.println("The Jaccard index is: " + jaccardValue);

    }
}