From cc54ff86f3dfb73fa608662a64ea4213ccba945d Mon Sep 17 00:00:00 2001
From: songyc macbook <gitea@gitea>
Date: Wed, 12 Nov 2025 20:20:41 +0900
Subject: [PATCH] 20251112 baekjoon

---
 code_study/Baekjoon/swift/9252.swift | 51 ++++++++++++++++++++++++++++
 1 file changed, 51 insertions(+)
 create mode 100644 code_study/Baekjoon/swift/9252.swift

diff --git a/code_study/Baekjoon/swift/9252.swift b/code_study/Baekjoon/swift/9252.swift
new file mode 100644
index 0000000..55f053f
--- /dev/null
+++ b/code_study/Baekjoon/swift/9252.swift
@@ -0,0 +1,51 @@
+if let in1 = readLine(), let in2 = readLine()
+{
+    let s1: [Character] = Array(in1)
+    let s2: [Character] = Array(in2)
+    let (l1, l2) = (s1.count, s2.count)
+    var dp: [[Int]] = Array(repeating: Array(repeating: 0, count: l2+1), count: l1+1)
+    
+    for i in 1...l1 {
+        
+        let c1 = s1[i-1]
+        
+        for j in 1...l2 {
+            
+            let c2 = s2[j-1]
+            
+            if c1 == c2 {
+                dp[i][j] = dp[i-1][j-1] + 1
+            }
+            else {
+                dp[i][j] = max(dp[i-1][j], dp[i][j-1])
+            }
+            
+        }
+    }
+    
+    print(dp[l1][l2])
+    
+    if dp[l1][l2] != 0 {
+        var result: String = ""
+        var (p1, p2) = (l1, l2)
+        
+        while !(p1 == 0 || p2 == 0) {
+            let (c1, c2) = (s1[p1-1], s2[p2-1])
+            
+            if c1 == c2 {
+                result.append(c1)
+                (p1, p2) = (p1-1, p2-1)
+            }
+            else {
+                if dp[p1-1][p2] > dp[p1][p2-1] {
+                    p1 -= 1
+                }
+                else {
+                    p2 -= 1
+                }
+            }
+        }
+        
+        print(String(Array(result).reversed()))
+    }
+}