StrongTest

package p20190916;

import junit.framework.TestCase;

import java.util.TreeSet;

public class StrongTest extends TestCase {

    public void testKnownStrongNumbersBetween0and999() {
        final TreeSet<Integer> strongNumbers = new TreeSet<>();
        assertIsStrongNumber(strongNumbers, 0);
        assertIsStrongNumber(strongNumbers, 1);
        assertIsStrongNumber(strongNumbers, 2);
        assertIsStrongNumber(strongNumbers, 145);
        assertIsStrongNumber(strongNumbers, 40585);

        for (int otherNumber = 0; otherNumber <= 99999; ++otherNumber) {
            if (!strongNumbers.contains(otherNumber)) {
                assertFalse(otherNumber + " should *NOT* be an Strong number", NumberFinder.isStrong(otherNumber));
            }
        }
    }

    private static void assertIsStrongNumber(TreeSet<Integer> strongNumbers, int strongNumber) {
        assertTrue(strongNumber + " should be Strong number", NumberFinder.isStrong(strongNumber));
        strongNumbers.add(strongNumber);
    }

}