Merge remote-tracking branch 'upstream/master'

1 files changed, 46 insertions, 0 deletions

diff --git a/challenge-238/deadmarshal/java/Ch2.java b/challenge-238/deadmarshal/java/Ch2.java
new file mode 100644
index 0000000000..0a71d431a4
--- /dev/null
+++ b/challenge-238/deadmarshal/java/Ch2.java
@@ -0,0 +1,46 @@
+import java.util.ArrayList;
+import java.util.Comparator;
+import java.util.List;
+
+public class Ch2 {
+  public static void main(String[] args) {
+    ArrayList<Integer> list1 = new ArrayList<>(List.of(15,99,1,34));
+    ArrayList<Integer> list2 = new ArrayList<>(List.of(50,25,33,22));
+    persistence_sort(list1);
+    persistence_sort(list2);
+    System.out.println(list1);
+    System.out.println(list2);
+  }
+
+  private static int product(int n) {
+    int prod = 1;
+    while(n > 0)
+    {
+      prod *= n % 10;
+      n /= 10;
+    }
+    return prod;
+  }
+
+  private static int helper(int n) {
+    int sum = 0;
+    while(n >= 10)
+    {
+      sum++;
+      n = product(n);
+    }
+    return sum;
+  }
+  
+  private static void persistence_sort(List<Integer> list) {
+    list.sort(new Comparator<Integer>() {
+      @Override
+      public int compare(Integer a, Integer b) {
+      	int ha = helper(a);
+      	int hb = helper(b);
+      	return ha == hb ? Integer.compare(a,b) : 
+	  Integer.compare(ha,hb);
+      }});
+  }
+}
+