From 8de503594bd2c01eb28d74f6c3a167fcbd2b4637 Mon Sep 17 00:00:00 2001
From: Haswatha Sridharan <haswathas@gmail.com>
Date: Wed, 21 May 2025 19:10:49 -0500
Subject: [PATCH 1/3] Completed Rank Scores

---
 README.md | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/README.md b/README.md
index c2318de..96799ed 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,11 @@
 # Sql2
 
 Problem 1 : Rank Scores		(https://leetcode.com/problems/rank-scores/ )
+Solution:
+
+Select score, DENSE_RANK()
+OVER (ORDER BY score DESC) AS 'rank'
+from Scores
 
 Problem 2 : Exchange Seats	(https://leetcode.com/problems/exchange-seats/ )
 

From 35e225bf9f554852dd819b5bd599367c945e327d Mon Sep 17 00:00:00 2001
From: Haswatha Sridharan <haswathas@gmail.com>
Date: Thu, 22 May 2025 19:02:14 -0500
Subject: [PATCH 2/3] Completed Exchange Seats

---
 README.md | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/README.md b/README.md
index 96799ed..194cbfc 100644
--- a/README.md
+++ b/README.md
@@ -8,6 +8,16 @@ OVER (ORDER BY score DESC) AS 'rank'
 from Scores
 
 Problem 2 : Exchange Seats	(https://leetcode.com/problems/exchange-seats/ )
+Solution:
+
+SELECT (
+    CASE 
+       WHEN MOD(id,2) != 0 AND id = cnts THEN id
+       WHEN MOD(id,2) != 0 AND id != cnts THEN id+1
+       ELSE id-1
+    END
+)AS 'id', student FROM seat, (SELECT COUNT(*) AS 'cnts' FROM Seat) AS seat_counts
+ORDER BY id
 
 Problem 3 : Tree Node		(https://leetcode.com/problems/tree-node/ )
 

From 4531fa6404c7d5b09e68af5f59feacc6ad5f8d90 Mon Sep 17 00:00:00 2001
From: Haswatha Sridharan <haswathas@gmail.com>
Date: Tue, 27 May 2025 19:44:59 -0500
Subject: [PATCH 3/3] Completed Tree Node & Deparment Top 3 Salaries

---
 README.md | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/README.md b/README.md
index 194cbfc..ea4d712 100644
--- a/README.md
+++ b/README.md
@@ -20,5 +20,28 @@ SELECT (
 ORDER BY id
 
 Problem 3 : Tree Node		(https://leetcode.com/problems/tree-node/ )
+Solution:
+
+Select id, (
+    CASE
+        when p_id IS Null 
+        then "Root"
+        when id In (Select Distinct p_id from tree ) then "Inner"
+        else "Leaf"
+    end) AS type
+from Tree
+order by id ASC
 
 Problem 4 : Deparment Top 3 Salaries		(https://leetcode.com/problems/department-top-three-salaries/ )
+Solution:
+
+SELECT d.name AS Department, e.name AS Employee, e.salary AS Salary
+FROM Employee e
+JOIN Department d ON e.departmentId = d.id
+WHERE 3 > (
+    SELECT COUNT(DISTINCT e2.salary)
+    FROM Employee e2
+    WHERE e2.departmentId = e.departmentId
+      AND e2.salary > e.salary
+)
+ORDER BY d.name, e.salary DESC;
\ No newline at end of file