1 files changed, 12 insertions, 0 deletions
diff --git a/Test/textbook/McCarthy-91.bpl b/Test/textbook/McCarthy-91.bpl
new file mode 100644
index 00000000..899a7ff1
--- /dev/null
+++ b/Test/textbook/McCarthy-91.bpl
@@ -0,0 +1,12 @@
+// McCarthy 91 function
+procedure F(n: int) returns (r: int)
+  ensures 100 < n ==> r == n - 10;
+  ensures n <= 100 ==> r == 91;
+{
+  if (100 < n) {
+    r := n - 10;
+  } else {
+    call r := F(n + 11);
+    call r := F(r);
+  }
+}