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src/server.c

@@ -129,11 +129,11 @@ int main(void) {
 int get_next_free_client_id(void) {
     for (int i = 0; i < MAX_CLIENTS; i++) {
         if (clients[i].id == -1) {
-            return i;
+            return i; // i is one below the id where -1 was found
         }
     }
 
-    return -1;
+    return -1; // Error: reached end of array
 }
 
 /* Thread, parses and handles messages */