From ebb7f9ba04c38fd950f82beb54f962a7d71b1282 Mon Sep 17 00:00:00 2001
From: Frederick Chen <seventeen@ohdragonboi.cn>
Date: Sat, 19 Apr 2025 10:09:51 +0800
Subject: [PATCH] AtCoder Beginner Contest 391

https://atcoder.jp/contests/abc391

Signed-off-by: Frederick Chen <seventeen@ohdragonboi.cn>
---
 atcoder/abc391/A_Lucky_Direction.cpp  | 30 +++++++++++++++++
 atcoder/abc391/B_Seek_Grid.cpp        | 48 +++++++++++++++++++++++++++
 atcoder/abc391/C_Pigeonhole_Query.cpp | 32 ++++++++++++++++++
 3 files changed, 110 insertions(+)
 create mode 100644 atcoder/abc391/A_Lucky_Direction.cpp
 create mode 100644 atcoder/abc391/B_Seek_Grid.cpp
 create mode 100644 atcoder/abc391/C_Pigeonhole_Query.cpp

diff --git a/atcoder/abc391/A_Lucky_Direction.cpp b/atcoder/abc391/A_Lucky_Direction.cpp
new file mode 100644
index 0000000..c264b1e
--- /dev/null
+++ b/atcoder/abc391/A_Lucky_Direction.cpp
@@ -0,0 +1,30 @@
+#include <bits/stdc++.h>
+#define lo long long
+#define INF INT_MAX
+#define LLM LONG_LONG_MAX
+
+using namespace std;
+const int N = 1e7 + 10;
+/*
+    toothless. #17
+    @fredcss_dev
+*/
+
+map<string, string> mp;
+
+string n;
+
+signed main()
+{
+    mp["N"] = "S";
+    mp["E"] = "W";
+    mp["W"] = "E";
+    mp["S"] = "N";
+    mp["NE"] = "SW";
+    mp["NW"] = "SE";
+    mp["SE"] = "NW";
+    mp["SW"] = "NE";
+    cin >> n;
+    cout << mp[n];
+    return 0;
+}
\ No newline at end of file
diff --git a/atcoder/abc391/B_Seek_Grid.cpp b/atcoder/abc391/B_Seek_Grid.cpp
new file mode 100644
index 0000000..f66753e
--- /dev/null
+++ b/atcoder/abc391/B_Seek_Grid.cpp
@@ -0,0 +1,48 @@
+#include <bits/stdc++.h>
+#define lo long long
+#define INF INT_MAX
+#define LLM LONG_LONG_MAX
+
+using namespace std;
+const int N = 1e7 + 10;
+/*
+    toothless. #17
+    @fredcss_dev
+*/
+
+signed main() {
+    int N, M;
+    cin >> N >> M;
+
+    vector<vector<char> > S(N, vector<char>(N));
+    vector<vector<char> > T(M, vector<char>(M));
+    for (int i = 0; i < N; ++i) {
+        for (int j = 0; j < N; ++j) {
+            cin >> S[i][j];
+        }
+    }
+    for (int i = 0; i < M; ++i) {
+        for (int j = 0; j < M; ++j) {
+            cin >> T[i][j];
+        }
+    }
+    for (int a = 0; a <= N - M; ++a) {
+        for (int b = 0; b <= N - M; ++b) {
+            bool match = true;
+            for (int i = 0; i < M; ++i) {
+                for (int j = 0; j < M; ++j) {
+                    if (S[a + i][b + j] != T[i][j]) {
+                        match = false;
+                        break;
+                    }
+                }
+                if (!match) break;
+            }
+            if (match) {
+                cout << a + 1 << " " << b + 1 << endl;
+            }
+        }
+    }
+
+    return 0;
+}
\ No newline at end of file
diff --git a/atcoder/abc391/C_Pigeonhole_Query.cpp b/atcoder/abc391/C_Pigeonhole_Query.cpp
new file mode 100644
index 0000000..cf6fd51
--- /dev/null
+++ b/atcoder/abc391/C_Pigeonhole_Query.cpp
@@ -0,0 +1,32 @@
+#include <iostream>
+#include <vector>
+using namespace std;
+
+int n, q, mp[10005], g[10005], cnt = 0, a, b, c;
+
+int main()
+{
+    cin >> n >> q;
+    for (int i = 0; i <= n; i++)
+    {
+        mp[i] = 1;
+        g[i] = i;
+    }
+    while (q--)
+    {
+        cin >> a;
+        if (a == 1)
+        {
+            cin >> b >> c;
+            if (mp[g[b]] == 2)
+                cnt--;
+            if (mp[c] == 1)
+                cnt++;
+            mp[g[b]]--;
+            mp[c]++;
+            g[b] = c;
+        }
+        else if (a == 2)
+            cout << cnt << endl;
+        return 0;
+    }
\ No newline at end of file