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--- kdp20260110-2 [May 13, 2026 at 18:01] – yanevskiv
+++ kdp20260110-2 [May 14, 2026 at 11:38] (current) – external edit 127.0.0.1
@@ Line 1: / Line 1: @@
+# KDP Midterm (2026-01-10) Question 2
+Consider a dining table that can seat at most $N$ people ($N > 2$). A person may take some food, sit at the table (`sitAtTable()`), eat, leave the table (`leaveTable()`) and walk away. No person should eat alone i.e. sit at the table alone. Also, every person that takes food must necessarily sit down in order to eat. Create a solution for this probalom using a *signal and wait* monitor. The monitor should only have two methods `sitAtTable()` and `leaveTable()`
+## Solution
+```c
+#define N ... /* N > 2 */
+monitor Table {
+    int count = 0;
+    cond wantToSit;
+    cond wantToLeave;
+    void sitAtTable() {
+        while (count == N)
+            wantToSit.wait();
+        count += 1;
+        if (count == 1)
+            wantToLeave.wait();
+    }
+    void leaveTable() {
+        while (count == 2)
+            wantToLeave.wait();
+        count -= 1;
+        if (count >= 2)
+            wantToLeave.signal();
+        wantToSit.signal();
+    }
+}
+```