Merge pull request #2915 from ash/master

Week 89 Task 1 and an Advent blog post

1 files changed, 29 insertions, 0 deletions

diff --git a/challenge-089/ash/java/ch-1.java b/challenge-089/ash/java/ch-1.java
new file mode 100644
index 0000000000..9e41cf211f
--- /dev/null
+++ b/challenge-089/ash/java/ch-1.java
@@ -0,0 +1,29 @@
+// To run:
+// $ java ch-1.java 100
+// 13015
+
+class Main {
+    static int gcd(int a, int b) {
+        while (b != 0) {
+            int t = b;
+            b = a % b;
+            a = t;
+        }
+
+        return a;
+    }
+
+    public static void main(String[] args) {
+        int n = args.length == 1 ? Integer.parseInt(args[0]) : 3;
+
+        int s = 0;
+        for (int x = 1; x <= n; x++) {
+            for (int y = x + 1; y <= n; y++) {
+
+                s += gcd(x, y);
+            }
+        }
+
+        System.out.println(s);
+    }
+}