From accd7fe48fe40a9508380b5fe42f2e0a93ae42c6 Mon Sep 17 00:00:00 2001
From: sh0723 <pshpark12345@naver.com>
Date: Mon, 29 Jun 2026 17:45:41 +0900
Subject: [PATCH 1/2] =?UTF-8?q?1285=20:=20=EB=8F=99=EC=A0=84=20=EB=92=A4?=
 =?UTF-8?q?=EC=A7=91=EA=B8=B0=20v1=20solve?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 src/week4/BOJ1285/BOJ1285_V1.cpp | 52 ++++++++++++++++++++++++++++++++
 1 file changed, 52 insertions(+)
 create mode 100644 src/week4/BOJ1285/BOJ1285_V1.cpp

diff --git a/src/week4/BOJ1285/BOJ1285_V1.cpp b/src/week4/BOJ1285/BOJ1285_V1.cpp
new file mode 100644
index 0000000..7799ee1
--- /dev/null
+++ b/src/week4/BOJ1285/BOJ1285_V1.cpp
@@ -0,0 +1,52 @@
+#include <bits/stdc++.h>
+using namespace std;
+bool bitmap[20][20];
+int N;
+int ret = INT_MAX;
+int calculate() {
+    int cnt = 0;
+    for (int i = 0; i < N; i++) {
+        int t=0;
+        for (int j = 0; j < N; j++) {
+            if (bitmap[j][i]) t++;
+        }
+        cnt += min(t, N-t);
+    }
+    return cnt;
+}
+void flip(int row) {
+    for (int i = 0; i < N; i++) {
+        bitmap[row][i] = !bitmap[row][i];
+    }
+}
+void solve(int st) {
+    if (st == N) {
+        ret = min(ret, calculate());
+        return;
+    }
+    solve(st+1);
+    flip(st);
+    solve(st+1);
+    flip(st);
+}
+int main() {
+
+    ios_base::sync_with_stdio(false);
+    cin.tie(NULL);
+    cout.tie(NULL);
+
+    cin >> N;
+    for (int i=0; i<N; i++) {
+        string s;
+        cin >> s;
+        for (int j=0; j<N; j++) {
+            bitmap[i][j] = (s[j] == 'T'); // 뒷면 true
+        }
+    }
+
+    solve(0);
+
+    cout << ret << '\n';
+
+    return 0;
+}
\ No newline at end of file

From e8e4cc6fccf4e5a3ceb9a9738990722221a2f609 Mon Sep 17 00:00:00 2001
From: sh0723 <pshpark12345@naver.com>
Date: Mon, 29 Jun 2026 17:58:17 +0900
Subject: [PATCH 2/2] =?UTF-8?q?1285=20:=20=EB=8F=99=EC=A0=84=20=EB=92=A4?=
 =?UTF-8?q?=EC=A7=91=EA=B8=B0=20v2=20solve?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 src/week4/BOJ1285/BOJ1285_V2.cpp | 51 ++++++++++++++++++++++++++++++++
 1 file changed, 51 insertions(+)
 create mode 100644 src/week4/BOJ1285/BOJ1285_V2.cpp

diff --git a/src/week4/BOJ1285/BOJ1285_V2.cpp b/src/week4/BOJ1285/BOJ1285_V2.cpp
new file mode 100644
index 0000000..39d97c9
--- /dev/null
+++ b/src/week4/BOJ1285/BOJ1285_V2.cpp
@@ -0,0 +1,51 @@
+#include <bits/stdc++.h>
+using namespace std;
+int N;
+int inp[21];
+int ret = INT_MAX;
+int calculate() {
+    int sum = 0;
+    for (int i=1; i<=(1 << (N-1)); i*=2) {
+        int cnt = 0;
+        for (int j=1; j<=N; j++) {
+            if (inp[j] & i) cnt++;
+        }
+        sum += min(cnt, N-cnt);
+    }
+    return sum;
+}
+void solve(int st) {
+    if (st == N+1) {
+        ret = min(ret, calculate());
+        return;
+    }
+
+    solve(st+1);
+    inp[st] = ~inp[st];
+    solve(st+1);
+    inp[st] = ~inp[st];
+}
+int main() {
+
+    ios_base::sync_with_stdio(false);
+    cin.tie(NULL);
+    cout.tie(NULL);
+
+    cin >> N;
+
+    for (int i = 1; i <= N; i++) {
+        string s;
+        cin >> s;
+        int tmp = 1;
+        for (int j=0; j<s.length(); j++) {
+            if (s[j] == 'T')inp[i] |= tmp;
+            tmp *= 2;
+        }
+    }
+
+    solve(1);
+
+    cout << ret << '\n';
+
+    return 0;
+}
\ No newline at end of file