20240930 finished.

src/problem/mod.rs

@@ -250,3 +250,4 @@ mod p2535_difference_between_element_sum_and_digit_sum_of_an_array;
 mod p2516_take_k_of_each_character_from_left_and_right;
 mod p2286_booking_concert_tickets_in_groups;
 mod p2073_time_needed_to_buy_tickets;
+mod p1845_seat_reservation_manager;

src/problem/p1845_seat_reservation_manager.rs

@@ -0,0 +1,61 @@
+/**
+ * [1845] Seat Reservation Manager
+ */
+pub struct Solution {}
+
+// submission codes start here
+use std::collections::BinaryHeap;
+use std::cmp::Reverse;
+
+struct SeatManager {
+    seats: BinaryHeap<Reverse<i32>>
+}
+
+/**
+ * `&self` means the method takes an immutable reference.
+ * If you need a mutable reference, change it to `&mut self` instead.
+ */
+impl SeatManager {
+
+    fn new(n: i32) -> Self {
+        let mut heap = BinaryHeap::with_capacity(n as usize);
+        
+        for i in 1..=n {
+            heap.push(Reverse(i));
+        }
+        
+        Self {
+            seats: heap
+        }
+    }
+    
+    fn reserve(&mut self) -> i32 {
+        let head = self.seats.pop();
+        head.unwrap().0
+    }
+    
+    fn unreserve(&mut self, seat_number: i32) {
+        self.seats.push(Reverse(seat_number));
+    }
+}
+
+/**
+ * Your SeatManager object will be instantiated and called as such:
+ * let obj = SeatManager::new(n);
+ * let ret_1: i32 = obj.reserve();
+ * obj.unreserve(seatNumber);
+ */
+
+// submission codes end
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_1845() {
+        let mut manager = SeatManager::new(5);
+        
+        assert_eq!(1, manager.reserve());
+    }
+}