Merge remote-tracking branch 'upstream/master'

1 files changed, 23 insertions, 0 deletions

diff --git a/challenge-285/deadmarshal/java/Ch1.java b/challenge-285/deadmarshal/java/Ch1.java
new file mode 100644
index 0000000000..8b8f8229f4
--- /dev/null
+++ b/challenge-285/deadmarshal/java/Ch1.java
@@ -0,0 +1,23 @@
+import java.util.HashMap;
+import java.util.Map;
+
+public class Ch1 {
+  public static void main(String[] args) {
+    String[][] arr1 = {{"B", "C"}, {"D", "B"}, {"C", "A"}};
+    String[][] arr2 = {{"A", "Z"}};
+    System.out.println(no_connection(arr1));
+    System.out.println(no_connection(arr2));
+  }
+
+  private static String no_connection(String[][] arr) {
+    Map<String, Integer> destinations = new HashMap<>(),
+      sources = new HashMap<>();
+    for (String[] a : arr) {
+      sources.put(a[0], 1);
+      destinations.put(a[1], 1);
+    }
+    for (String d : destinations.keySet())
+      if (!sources.containsKey(d)) return d;
+    return "";
+  }
+}