Finds all (integer) the triples from zero to max. won't return duplicates (ie. (3,4,5) and (4,3,5)) prints them
demonstrates:
nested loops,
multiple classes,
proper equals(Object) override (no hashcode though),
writing to file

/**creates pythagorian triples. SciWizEH*/
public class Tripler
{
    static java.io.PrintWriter f; // = new java.io.FileWriter("triples.txt");
    static int max = 1000; 
    static boolean add = true;
    static int count;
    static java.util.ArrayList < Triple > ts = 
        new java.util.ArrayList < Triple > ();
    /**main.*/
    public static void main(String[] args) {
        ts.clear();
        count = 0;
        for (int a = 1; a <= max; a++) {
            for (int b = 1; b <= max; b++) {
                for (int c = 1; c <= max; c++) {
                    add = true;
                    if (((a * a) + (b * b)) == (c * c)) {
                        Triple t  = new Triple(a, b, c);
                        for (Triple x : ts) {
                            if (t.equals(x)) {
                                add = false;
                            }
                        }
                        if (add) {
                            ts.add(t);
                        }
                    }
                }
            }
        }
        try {
            String str = "";
            f = new java.io.PrintWriter(new java.io.FileWriter("triples.txt"));
            for (Triple y : ts) {
                f.println(y.toString());
                Triple.print(y);
                count++;
            }
            f.println(count + "");
            System.out.println(count + "");
            f.close();
        } 
        catch (Exception e) {
            //dd
        }
    }
}
/**clas to handle triples*/
class Triple {
	/**a part.*/
	public int a ;
	/**b part.*/
	public int b ;
	/**c part.*/
	public int c ;

	/**
	 * Costructor for objects of class triple.
	 */
	public Triple ( int na , int nb , int nc ) {
		a = na ;
		b = nb ;
		c = nc ;
	}

	/**
	 * checks if it equals another, or is a multiple of it.
	 */
	@Override
	public boolean equals ( Object n ) {
		if ( n == null ) {
			return false ;
		}
		if ( n.getClass ( ) == getClass ( ) ) {
			Triple nt = ( Triple ) n ;
			if ( ( a == nt.a || a == nt.b ) && ( b == nt.b || b == nt.a )
					&& ( c == nt.c ) ) {
				return true ;
			} else if ( ( ( ( ( a % nt.a ) == 0 ) || ( ( nt.a % a ) == 0 ) ) || ( ( ( a % nt.b ) == 0 ) || ( ( nt.b % a ) == 0 ) ) )
					&& ( ( ( ( b % nt.b ) == 0 ) || ( ( nt.b % b ) == 0 ) ) || ( ( ( b % nt.a ) == 0 ) || ( ( nt.a % b ) == 0 ) ) )
					&& ( ( c % nt.c ) == 0 || ( nt.c % c ) == 0 ) ) {
				return true ;
			} else {
				return false ;
			}
		} else {
			return false ;
		}
	}

	/**
	 * prints one to system.
	 */
	static void print ( Triple nt ) {
		System.out.println ( nt.a + ", " + nt.b + ", " + nt.c ) ;
	}

	/**
	 * makes a string of this triple.
	 */
	public String toString ( ) {
		return a + ", " + b + ", " + c ;
	}
}
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