diff --git a/r2.py b/r2.py
new file mode 100644
index 0000000..f63bc35
--- /dev/null
+++ b/r2.py
@@ -0,0 +1,7 @@
+import sys
+
+r1, s = sys.stdin.readline().split(' ')
+r1 = int(r1)
+s = int(s)
+
+print(s*2 - r1)