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--- kdp20260218-1 [May 13, 2026 at 18:21] – yanevskiv
+++ kdp20260218-1 [May 14, 2026 at 11:38] (current) – external edit 127.0.0.1
@@ Line 1: / Line 1: @@
+# KDP Exam (2026-02-18) Question 1
+Solve the dining philsophers problem by using *signal and continue* monitor discipline and by using *covering condition* technique. Ensure philosphers start eating in the order of their arrival.
+## Solution
+```c
+#define N 5 /* number of philosophers */
+monitor DiningPhilosophers {
+    enum { THINKING, HUNGRY, EATING };
+    int phil[N];
+    cond delay[N];
+    queue<int> q;
+    bool canEat(int id) {
+        return (phil[(id - 1 + N) % N] != EATING) && (phil[(id + 1) % N] != EATING)
+    }
+    void pickup(int id) {
+        phil[id] = HUNGRY;
+        queue.push(id);
+        while (q.front() != id || ! canEat(id))
+            delay[id].wait();
+        q.pop();
+        phil[id] = EATING;
+    }
+    void putdown(int id) {
+        phil[id] = THINKING;
+        for (int i = 0; i < N; i += 1)
+            delay[i].signal();
+    }
+}
+```