diff --git a/lcci/17.08.Circus Tower/README.md b/lcci/17.08.Circus Tower/README.md
index 7dc55088a28c3..24f5cecfecf83 100644
--- a/lcci/17.08.Circus Tower/README.md	
+++ b/lcci/17.08.Circus Tower/README.md	
@@ -239,6 +239,68 @@ func bestSeqAtIndex(height []int, weight []int) int {
 }
 ```
 
+```swift
+class BinaryIndexedTree {
+    private var n: Int
+    private var c: [Int]
+
+    init(_ n: Int) {
+        self.n = n
+        self.c = [Int](repeating: 0, count: n + 1)
+    }
+
+    func update(_ x: Int, _ val: Int) {
+        var x = x
+        while x <= n {
+            c[x] = max(c[x], val)
+            x += x & -x
+        }
+    }
+
+    func query(_ x: Int) -> Int {
+        var x = x
+        var s = 0
+        while x > 0 {
+            s = max(s, c[x])
+            x -= x & -x
+        }
+        return s
+    }
+}
+
+class Solution {
+    func bestSeqAtIndex(_ height: [Int], _ weight: [Int]) -> Int {
+        let n = height.count
+        var arr: [(Int, Int)] = []
+        for i in 0..<n {
+            arr.append((height[i], weight[i]))
+        }
+        arr.sort {
+            if $0.0 == $1.0 {
+                return $1.1 < $0.1
+            }
+            return $0.0 < $1.0
+        }
+
+        let weights = Set(arr.map { $1 })
+        let sortedWeights = Array(weights).sorted()
+        let m = sortedWeights.enumerated().reduce(into: [Int: Int]()) {
+            $0[$1.element] = $1.offset + 1
+        }
+
+        let tree = BinaryIndexedTree(sortedWeights.count)
+        var ans = 1
+        for (_, w) in arr {
+            let x = m[w]!
+            let t = tree.query(x - 1) + 1
+            ans = max(ans, t)
+            tree.update(x, t)
+        }
+        return ans
+    }
+}
+```
+
 <!-- tabs:end -->
 
 <!-- end -->
diff --git a/lcci/17.08.Circus Tower/README_EN.md b/lcci/17.08.Circus Tower/README_EN.md
index 98c6e9671528e..dc6d34efff6c4 100644
--- a/lcci/17.08.Circus Tower/README_EN.md	
+++ b/lcci/17.08.Circus Tower/README_EN.md	
@@ -242,6 +242,68 @@ func bestSeqAtIndex(height []int, weight []int) int {
 }
 ```
 
+```swift
+class BinaryIndexedTree {
+    private var n: Int
+    private var c: [Int]
+
+    init(_ n: Int) {
+        self.n = n
+        self.c = [Int](repeating: 0, count: n + 1)
+    }
+
+    func update(_ x: Int, _ val: Int) {
+        var x = x
+        while x <= n {
+            c[x] = max(c[x], val)
+            x += x & -x
+        }
+    }
+
+    func query(_ x: Int) -> Int {
+        var x = x
+        var s = 0
+        while x > 0 {
+            s = max(s, c[x])
+            x -= x & -x
+        }
+        return s
+    }
+}
+
+class Solution {
+    func bestSeqAtIndex(_ height: [Int], _ weight: [Int]) -> Int {
+        let n = height.count
+        var arr: [(Int, Int)] = []
+        for i in 0..<n {
+            arr.append((height[i], weight[i]))
+        }
+        arr.sort {
+            if $0.0 == $1.0 {
+                return $1.1 < $0.1
+            }
+            return $0.0 < $1.0
+        }
+
+        let weights = Set(arr.map { $1 })
+        let sortedWeights = Array(weights).sorted()
+        let m = sortedWeights.enumerated().reduce(into: [Int: Int]()) {
+            $0[$1.element] = $1.offset + 1
+        }
+
+        let tree = BinaryIndexedTree(sortedWeights.count)
+        var ans = 1
+        for (_, w) in arr {
+            let x = m[w]!
+            let t = tree.query(x - 1) + 1
+            ans = max(ans, t)
+            tree.update(x, t)
+        }
+        return ans
+    }
+}
+```
+
 <!-- tabs:end -->
 
 <!-- end -->
diff --git a/lcci/17.08.Circus Tower/Solution.swift b/lcci/17.08.Circus Tower/Solution.swift
new file mode 100644
index 0000000000000..5d880cde599b7
--- /dev/null
+++ b/lcci/17.08.Circus Tower/Solution.swift	
@@ -0,0 +1,59 @@
+class BinaryIndexedTree {
+    private var n: Int
+    private var c: [Int]
+
+    init(_ n: Int) {
+        self.n = n
+        self.c = [Int](repeating: 0, count: n + 1)
+    }
+
+    func update(_ x: Int, _ val: Int) {
+        var x = x
+        while x <= n {
+            c[x] = max(c[x], val)
+            x += x & -x
+        }
+    }
+
+    func query(_ x: Int) -> Int {
+        var x = x
+        var s = 0
+        while x > 0 {
+            s = max(s, c[x])
+            x -= x & -x
+        }
+        return s
+    }
+}
+
+class Solution {
+    func bestSeqAtIndex(_ height: [Int], _ weight: [Int]) -> Int {
+        let n = height.count
+        var arr: [(Int, Int)] = []
+        for i in 0..<n {
+            arr.append((height[i], weight[i]))
+        }
+        arr.sort {
+            if $0.0 == $1.0 {
+                return $1.1 < $0.1
+            }
+            return $0.0 < $1.0
+        }
+
+        let weights = Set(arr.map { $1 })
+        let sortedWeights = Array(weights).sorted()
+        let m = sortedWeights.enumerated().reduce(into: [Int: Int]()) {
+            $0[$1.element] = $1.offset + 1
+        }
+
+        let tree = BinaryIndexedTree(sortedWeights.count)
+        var ans = 1
+        for (_, w) in arr {
+            let x = m[w]!
+            let t = tree.query(x - 1) + 1
+            ans = max(ans, t)
+            tree.update(x, t)
+        }
+        return ans
+    }
+}