[20251010] BOJ / G4 / 램프 / 김민진

zinnnn37/202510/10 BOJ G4 램프.md

@@ -0,0 +1,70 @@
+```java
+package etc;
+
+import java.io.*;
+import java.util.StringTokenizer;
+
+public class BJ_1034_램프 {
+
+    private static final BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+    private static final BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
+    private static StringTokenizer st;
+
+    private static int N, M, K, max;
+    private static boolean[][] lamp;
+
+    public static void main(String[] args) throws IOException {
+        init();
+        sol();
+    }
+
+    private static void init() throws IOException {
+        st = new StringTokenizer(br.readLine());
+        N = Integer.parseInt(st.nextToken());
+        M = Integer.parseInt(st.nextToken());
+
+        lamp = new boolean[N][M];
+        for (int i = 0; i < N; i++) {
+            String s = br.readLine();
+            for (int j = 0; j < M; j++) {
+                lamp[i][j] = s.charAt(j) == '1';
+            }
+        }
+
+        K = Integer.parseInt(br.readLine());
+        max = 0;
+    }
+
+    private static void sol() throws IOException {
+        for (int i = 0; i < N; i++) {
+            int toTurnOn = 0;
+
+            for (int j = 0; j < M; j++) {
+                if (!lamp[i][j]) toTurnOn++;
+            }
+
+            // (K - 켜야 하는 열의 수)가 홀수면 켜지 않아야 할 다른 열도 켜지기 때문에 걸러야 함
+            if (toTurnOn > K || (K - toTurnOn) % 2 != 0) continue;
+
+            // 행 개수 세기
+            int cnt = 0;
+            for (int k = 0; k < N; k++) {
+                if (isAllTurnedOn(i, k)) cnt++;
+            }
+            max = Math.max(max, cnt);
+        }
+        bw.write(max + "\n");
+        bw.flush();
+        bw.close();
+        br.close();
+    }
+
+    private static boolean isAllTurnedOn(int row1, int row2) {
+        for (int j = 0; j < M; j++) {
+            if (lamp[row1][j] != lamp[row2][j]) return false;
+        }
+        return true;
+    }
+
+}
+```