[20250213] BOJ / 골드5 / 톱니바퀴(2) / 설진영

Seol-JY/202502/13 BOJ G5 톱니바퀴(2).md

@@ -0,0 +1,75 @@
+```java
+import java.io.*;
+import java.util.*;
+public class Main {
+    private static int count = 0;
+    public static void main(String[] args) throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+
+        int T = Integer.parseInt(br.readLine());
+        int[] arr = new int[T];
+
+        for (int i = 0; i < T; i++) {
+            arr[i] = Integer.parseInt(br.readLine(), 2);
+        }
+
+        int K = Integer.parseInt(br.readLine());
+
+        for (int i = 0; i < K; i++) {
+            StringTokenizer st = new StringTokenizer(br.readLine());
+            int index = Integer.parseInt(st.nextToken()) - 1;
+            int direction = Integer.parseInt(st.nextToken());
+
+            int[] turns = new int[T];
+            turns[index] = direction;
+
+            for (int j = index - 1; j >= 0; j--) {
+                if (needTurn(arr[j], arr[j+1])) {
+                    turns[j] = -turns[j+1];
+                } else {
+                    break;
+                }
+            }
+            for (int j = index + 1; j < T; j++) {
+                if (needTurn(arr[j-1], arr[j])) {
+                    turns[j] = -turns[j-1];
+                } else {
+                    break;
+                }
+            }
+
+            for (int j = 0; j < T; j++) {
+                if (turns[j] == 1) {
+                    arr[j] = clockwise(arr[j]);
+                } else if (turns[j] == -1) {
+                    arr[j] = antiClockwise(arr[j]);
+                }
+            }
+        }
+        int answer = 0;
+        for (int i = 0; i < T; i++) {
+            if ((arr[i] & 128) == 128) {
+                answer++;
+            }
+        }
+        System.out.println(answer);
+    }
+
+
+    // 회전 여부 결정
+    private static boolean needTurn(Integer left, Integer right) {
+        return ((left & 32) == 32) != ((right & 2) == 2);
+    }
+
+    // 회전시키기
+    private static Integer clockwise(Integer target) {
+        int adjust = ((target & 1) == 1) ? 128 : 0;
+        return (target >> 1) + adjust;
+    }
+
+    private static Integer antiClockwise(Integer target) {
+        int adjust = ((target & 128) == 128) ? -255 : 0;
+        return (target << 1) + adjust;
+    }
+}
+```