diff --git a/rb/1A.rb b/rb/1A.rb
new file mode 100644
index 0000000..3816ab5
--- /dev/null
+++ b/rb/1A.rb
@@ -0,0 +1,6 @@
+n, m, a = gets.split.map(&:to_i)
+
+tiles_n = (n + a - 1) / a
+tiles_m = (m + a - 1) / a
+
+puts tiles_n * tiles_m