[20250810] BOJ / G4 / A를 B로 / 이종환

Author: 0224LJH

0224LJH/202508/10 BOJ A를 B로.md

@@ -0,0 +1,70 @@
+```java
+import java.awt.*;
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.*;
+import java.util.List;
+
+
+public class Main {
+    static String target,goal;
+
+    static int size,ans;
+    static int[] arr;
+
+    static List<Character> list = new ArrayList<>();
+
+    public static void main(String[] args) throws IOException {
+        init();
+        process();
+        print();
+    }
+
+    private static void init() throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        target = br.readLine();
+        goal = br.readLine();
+        ans = 0;
+    }
+
+    private static void process() throws IOException {
+
+        int goalIdx = goal.length()-1;
+
+        for (int i = target.length()-1; i >= 0; i--) {
+            if (target.charAt(i) == goal.charAt(goalIdx)) {
+                goalIdx--;
+            } else {
+                list.add(target.charAt(i));
+                ans++;
+            }
+        }
+
+        if (goalIdx == -1) return;
+
+        Outer:
+        while (goalIdx >= 0) {
+            for (int i = 0; i < list.size(); i++) {
+                Character c = list.get(i);
+                if (c==goal.charAt(goalIdx)) {
+                    goalIdx--;
+                    list.remove(i);
+                    continue Outer;
+                }
+            }
+
+            goalIdx--;
+
+        }
+
+        if (list.size() != 0) ans = -1;
+
+    }
+
+
+    private static void print() {
+        System.out.println(ans);
+    }
+}
+```