Add FiboBin exercise

HW01/FiboBin_06.java

@@ -0,0 +1,74 @@
+import java.util.Scanner;
+
+public class FiboBin {
+
+    /**
+     * Computes the n-th Fibonacci number using recursion.
+     * This method is intended only for internal use and is not optimized.
+     *
+     * @param f index of Fibonacci number (must be >= 0)
+     * @return the n-th Fibonacci number
+     */
+    private static int Fib(int f){
+        if (f < 2) {
+            return 1;
+        }
+        int st = 1;
+        int sec =1;
+        int thi = 0;
+        for (int k = 3; k <= f; k ++){
+            thi = st + sec;
+            st = sec;
+            sec = thi;
+        }
+        return sec;
+    }
+
+    /**
+     * Counts the number of bits set to '1' in the binary representation of the given integer.
+     *
+     * @param b the input number (must be non-negative)
+     * @return the number of 1-bits in x
+     */
+    private  static int Bin(int b){
+        int ones = 0;
+        while (b > 0){
+            ones += b%2;
+            b = (int) b/2;
+        }
+        return ones;
+    }
+
+    /**
+     * Determines whether the given number n is a FiboBinary number.
+     *
+     * @param n the number to test (must be non-negative)
+     * @return true if fib(n) equals the number of ones in the binary form of n, false otherwise
+     */
+    public static boolean isFiboBin(int n){
+        int i = 1;
+        while (true){
+            int fib = Fib(i);
+            if (fib > n){
+                break;
+            }
+            int bin = Bin(fib);
+            if ( bin + fib == n){
+                return true;
+            }
+            i++;
+        }
+        return false;
+    }
+
+    public static void main(String[] args) {
+        Scanner sc = new Scanner(System.in);
+        int number = sc.nextInt();
+         if (isFiboBin(number)){
+             System.out.println(number+ " is FiboBinary.");
+         }
+         else{
+             System.out.println(number+ " is not FiboBinary.");
+         }
+    }
+}