diff --git a/src/problem/mod.rs b/src/problem/mod.rs
index 00d367e..9a16d98 100644
--- a/src/problem/mod.rs
+++ b/src/problem/mod.rs
@@ -488,3 +488,5 @@ mod p1742_maximum_number_of_balls_in_a_box;
 mod p1552_magnetic_force_between_two_balls;
 
 mod p1706_where_will_the_ball_fall;
+
+mod p1299_replace_elements_with_greatest_element_on_right_side;
diff --git a/src/problem/p1299_replace_elements_with_greatest_element_on_right_side.rs b/src/problem/p1299_replace_elements_with_greatest_element_on_right_side.rs
new file mode 100644
index 0000000..597e310
--- /dev/null
+++ b/src/problem/p1299_replace_elements_with_greatest_element_on_right_side.rs
@@ -0,0 +1,49 @@
+/**
+ * [1299] Replace Elements with Greatest Element on Right Side
+ */
+pub struct Solution {}
+
+// submission codes start here
+use std::collections::BinaryHeap;
+use std::iter::FromIterator;
+
+impl Solution {
+    pub fn replace_elements(arr: Vec<i32>) -> Vec<i32> {
+        let mut heap: BinaryHeap<(i32, usize)> =
+            BinaryHeap::from_iter(arr[1..].into_iter().enumerate().map(|(i, v)| (*v, i + 1)));
+
+        let mut result = Vec::with_capacity(arr.len());
+
+        for i in 0..arr.len() - 1 {
+            while let Some(head) = heap.peek() {
+                if head.1 > i {
+                    break;
+                }
+
+                heap.pop();
+            }
+            if let Some(head) = heap.peek() {
+                result.push(head.0);
+            }
+        }
+
+        result.push(-1);
+        result
+    }
+}
+
+// submission codes end
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_1299() {
+        assert_eq!(
+            vec![18, 6, 6, 6, 1, -1],
+            Solution::replace_elements(vec![17, 18, 5, 4, 6, 1])
+        );
+        assert_eq!(vec![-1], Solution::replace_elements(vec![400]));
+    }
+}