1 files changed, 78 insertions, 0 deletions
diff --git a/AceptaElReto/src/problemas/Problema100.java b/AceptaElReto/src/problemas/Problema100.java
new file mode 100644
index 0000000..723e2c6
--- /dev/null
+++ b/AceptaElReto/src/problemas/Problema100.java
@@ -0,0 +1,78 @@
+package problemas;
+/*
+ * Para cada caso de prueba, el programa indicará el número de vueltas
+ * que se debe dar a la rutina de Kaprekar para alcanzar el 6174.
+ * Para los números repdigits deberá escribir 8.
+ * Para la propia constante de Kaprekar deberá indicar 0.
+ */
+
+import java.util.Arrays;
+
+public class Problema100 {
+
+	public static void main(String[] args) {
+		
+		int counter;
+		final String KAPREKAR_STRING = "6174";
+		
+		for ( String arg: args ) {
+			//System.out.println("Input: " + arg);
+			if ( arg.equals(KAPREKAR_STRING) ) {
+				System.out.println(0);
+			}
+			else {
+				counter = 0;
+				while ( !arg.equals(KAPREKAR_STRING) && counter < 8 ) {
+					arg = nextKaprekar(arg);
+					counter++;
+					//System.out.println("Iteration " + counter + ": " + arg);
+				}
+				System.out.println(counter);
+			}
+			
+		}
+		
+	}
+
+	private static String nextKaprekar(String arg) {
+		char[] ascending = new char[4];
+		char[] chars = arg.toCharArray();
+		for ( int i = 0; i < 4; i++ ) {
+			if (!(i >= chars.length) ) {
+				ascending[i] = chars[i];
+			}
+			else {
+				ascending[i] = '0';
+			}
+		}
+		// Order the array in ascending order
+		Arrays.sort(ascending);
+		//System.out.println("Ascending ordered for " + arg + ": " + charArrayToString(ascending));
+		
+		// Compute new value
+		int ascendingInt = Character.getNumericValue(ascending[0])*1000
+							+ Character.getNumericValue(ascending[1])*100
+							+ Character.getNumericValue(ascending[2])*10
+							+ Character.getNumericValue(ascending[3]);
+		int descendingInt = Character.getNumericValue(ascending[3])*1000
+							+ Character.getNumericValue(ascending[2])*100
+							+ Character.getNumericValue(ascending[1])*10
+							+ Character.getNumericValue(ascending[0]);
+		//System.out.println("Result: " + String.valueOf(descendingInt - ascendingInt));
+		return String.valueOf(descendingInt - ascendingInt);
+	}
+	
+	/**
+	 * For testing.
+	 * @param charArray
+	 * @return String corresponding to charArray.
+	 */
+	/*public static String charArrayToString(char[] charArray) {
+		String result = "";
+		for ( int i = 0; i < charArray.length; i++ ) {
+			result += String.valueOf(Character.getNumericValue(charArray[i]));
+		}
+		return result;
+	}*/
+	
+}