class AmstringBruteForce {
 
    public static void main( final String[] args ) {
        printAll( 2, "abbab", "aabba" );
    }
 
    private static void printAll( final int d, final String s1, final String s2 ) {
        for ( int len = 1; len <= s1.length(); len++ ) {
            for ( int s1s = 0; s1s <= s1.length() - len; s1s++ ) {
                for ( int s2s = 0; s2s <= s2.length() - len; s2s++ ) {
                    final String s1sub = s1.substring( s1s, s1s + len );
                    final String s2sub = s2.substring( s2s, s2s + len );
                    final int hd = getHammingDistance( s1sub, s2sub );
                    if ( hd <= d ) {
                        System.out.printf( "%s (%d), %s (%d) - %d\n", s1sub, s1s, s2sub, s2s, hd );
                    }
                }
            }
        }
    }
 
    private static int getHammingDistance( final String s1, final String s2 ) {
        assert ( s1.length() == s2.length() );
        int dist = 0;
        for ( int i = 0; i < s1.length(); i++ ) {
            if ( s1.charAt( i ) != s2.charAt( i ) ) ++dist;
        }
        return dist;
    }
 
}
 

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