Data update

Task/Cyclops-numbers/Java/cyclops-numbers.java

@@ -0,0 +1,132 @@
+import java.util.ArrayList;
+import java.util.List;
+
+public final class CyclopsNumbers {
+
+	public static void main(String[] args) {
+		List<Integer> cyclops = new ArrayList<Integer>();
+		List<Integer> primeCyclops = new ArrayList<Integer>();
+		List<Integer> blindPrimeCyclops = new ArrayList<Integer>();
+		List<Integer> palindromicPrimeCyclops = new ArrayList<Integer>();
+		
+		List<List<Integer>> ranges = List.of( List.of( 0, 0), List.of( 101, 909),
+			List.of( 11011, 99099 ), List.of( 1110111, 9990999 ), List.of( 111101111, 119101111 ) );
+		
+		for ( List<Integer> range : ranges) {
+			for ( int i = range.getFirst(); i <= range.getLast(); i++ ) {
+				String value = String.valueOf(i);
+				if ( isCyclopsNumber(value) ) {
+					cyclops.addLast(i);
+					if ( isPrime(i) ) {
+						primeCyclops.addLast(i);
+						if ( isBlind(value) ) {
+							blindPrimeCyclops.addLast(i);
+						}
+						if ( isPalindromic(value) ) {
+							palindromicPrimeCyclops.addLast(i);
+						}
+					}
+				}
+			}
+		}		
+		
+		System.out.println("The first 50 Cyclops numbers:");
+		for ( int i = 0; i < 50; i++ ) {
+			System.out.print(String.format("%6s%s", cyclops.get(i), ( i % 10 == 9 ? "\n" : "" )));
+		}
+		System.out.println();
+		int firstIndex = firstIndex(cyclops);
+		System.out.println("The first cyclops number greater than ten million is "
+			+ cyclops.get(firstIndex) + " at zero based index " + firstIndex);
+		System.out.println();
+		
+		System.out.println("The first 50 prime Cyclops numbers:");
+		for ( int i = 0; i < 50; i++ ) {
+			System.out.print(String.format("%7s%s", primeCyclops.get(i), ( i % 10 == 9 ? "\n" : "" )));
+		}
+		System.out.println();
+		firstIndex = firstIndex(primeCyclops);
+		System.out.println("The first prime cyclops number greater than ten million is "
+			+ primeCyclops.get(firstIndex) + " at zero based index " + firstIndex);
+		System.out.println();
+		
+		System.out.println("The first 50 blind prime Cyclops numbers:");
+		for ( int i = 0; i < 50; i++ ) {
+			System.out.print(String.format("%7s%s", blindPrimeCyclops.get(i), ( i % 10 == 9 ? "\n" : "" )));
+		}
+		System.out.println();
+		firstIndex = firstIndex(blindPrimeCyclops);
+		System.out.println("The first blind prime cyclops number greater than ten million is "
+			+ blindPrimeCyclops.get(firstIndex) + " at zero based index " + firstIndex);
+		System.out.println();
+		
+		System.out.println("The first 50 palindromic prime Cyclops numbers:");
+		for ( int i = 0; i < 50; i++ ) {
+			System.out.print(
+                String.format("%9s%s", palindromicPrimeCyclops.get(i), ( i % 10 == 9 ? "\n" : "" )));
+		}
+		System.out.println();
+		firstIndex = firstIndex(palindromicPrimeCyclops);
+		System.out.println("The first palindromic prime cyclops number greater than ten million is "
+			+ palindromicPrimeCyclops.get(firstIndex) + " at zero based index " + firstIndex);
+		System.out.println();		
+	}	
+	
+	private static int firstIndex(List<Integer> numbers) {
+		int start = 0;
+		int end = numbers.size() - 1;
+		while ( start <= end ) {
+	        final int mid = start + ( end - start ) / 2;
+	        if ( numbers.get(mid) <= 10_000_000 ) {
+	            start = mid + 1;
+	        } else {
+	            end = mid - 1;
+	        }
+	    }
+	    return start;
+	}	
+	
+	private static boolean isCyclopsNumber(String text) {
+		return text.charAt(text.length() / 2) == '0' && text.indexOf('0') == text.lastIndexOf('0');
+	}
+	
+	private static boolean isPalindromic(String text) {
+		for ( int i = 0; i < text.length() / 2; i++ ) {
+			if ( text.charAt(i) != text.charAt(text.length() - 1 - i) ) {
+				return false;
+			}
+		}
+		return true;
+	}
+	
+	private static boolean isBlind(String text) {
+		final int middle = text.length() / 2;
+		final String withoutZero = text.substring(0, middle) + text.substring(middle + 1);
+		return isPrime(Integer.valueOf(withoutZero));
+	}
+	
+	private static boolean isPrime(int number) {
+	    if ( number < 2 ) {
+	    	return false;
+	    }
+	    if ( number % 2 == 0 ) {
+	    	return number == 2;
+	    }
+	    if ( number % 3 == 0 ) {
+	    	return number == 3;
+	    }
+	    int k = 5;
+	    while ( k * k <= number ) {
+	    	if ( number % k == 0 ) {
+	    		return false;
+	    	}
+	    	k += 2;
+	    	if ( number % k == 0 ) {
+	    		return false;
+	    	}
+	    	k += 4;
+	    }
+	    return true;
+	}
+	
+}