1 files changed, 35 insertions, 0 deletions
diff --git a/java/somme.java b/java/somme.java
new file mode 100644
index 0000000..c1da9d5
--- /dev/null
+++ b/java/somme.java
@@ -0,0 +1,35 @@
+import java.util.Scanner;
+
+public class HelloWorld {
+    private static boolean pari(int n) {
+        return (n % 2) == 0;
+    }
+
+    private static int sequenza(int n, boolean pollatz, int tCollatz) {
+        int m = ((pollatz) ? 5 : 3), tot = 1;
+
+        while(n != 1) {
+            n = (pari(n)) ? n/2 : n*m+1;
+
+            tot++;
+
+            if(tCollatz != -1 && tot > tCollatz)
+                break;
+        }
+
+        return tot;
+    }
+
+    public static void main(String[] args) {
+        Scanner in = new Scanner(System.in);
+        int N1 = in.nextInt(), N2 = in.nextInt(), tot = 0, collatz;
+
+        for(int i = N1; i <= N2; i++) {
+            collatz = sequenza(i, false, -1);
+            if(sequenza(i, true, collatz) < collatz )
+                tot++;
+        }
+
+        System.out.println(tot);
+    }
+}