18 files changed, 949 insertions, 0 deletions
diff --git a/contests/Round894/A/main b/contests/Round894/A/main
new file mode 100755
index 0000000..725ccb1
--- /dev/null
+++ b/contests/Round894/A/main
diff --git a/contests/Round894/A/main.cpp b/contests/Round894/A/main.cpp
new file mode 100755
index 0000000..ca50590
--- /dev/null
+++ b/contests/Round894/A/main.cpp
@@ -0,0 +1,151 @@
+#include <bits/stdc++.h>
+using namespace std;
+
+using ll = long long;
+using pii = pair<int, int>;
+using vpi = vector<pii>;
+using vi = vector<int>;
+using vll = vector<long long>;
+using mpii = map<int, int>;
+using mpll = map<ll, ll>;
+using db = long double;
+
+#define pb push_back
+#define all(x) (x).begin(), (x).end()
+#define rall(x) (x).rbegin(), (x).rend()
+#define lb lower_bound
+#define ub upper_bound
+#define make_unique(x)                                                         \
+  sort(all((x)));                                                              \
+  \ (x).resize(unique(all((x))) - (x).begin())
+#define ceil(a, b) ((a) + (b)-1) / (b)
+
+const int MOD = (int)1e9 + 7;
+const db PI = acos((db)-1);
+const int dx[4]{1, 0, -1, 0};
+const int dy[4]{0, 1, 0, -1};
+
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const pair<K, V> &p);
+template <typename T> ostream &operator<<(ostream &os, const vector<T> &vec);
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const map<K, V> &m);
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const unordered_map<K, V> &m);
+template <typename T> ostream &operator<<(ostream &os, const set<T> &s);
+template <typename T>
+ostream &operator<<(ostream &os, const unordered_set<T> &s);
+
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const pair<K, V> &p) {
+  os << "(" << p.first << ", " << p.second << ")";
+  return os;
+}
+
+template <typename T> ostream &operator<<(ostream &os, const vector<T> &vec) {
+  os << "{";
+  for (size_t i = 0; i < vec.size(); ++i) {
+    if (i > 0)
+      os << ", ";
+    os << vec[i];
+  }
+  os << "}";
+  return os;
+}
+
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const map<K, V> &m) {
+  os << "{";
+  for (const auto &p : m) {
+    os << p.first << ": " << p.second << ", ";
+  }
+  os << "}";
+  return os;
+}
+
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const unordered_map<K, V> &m) {
+  os << "{";
+  for (const auto &p : m) {
+    os << p.first << ": " << p.second << ", ";
+  }
+  os << "}";
+  return os;
+}
+
+template <typename T> ostream &operator<<(ostream &os, const set<T> &s) {
+  int i = 0;
+  os << "{";
+  for (const auto &e : s) {
+    if (i > 0)
+      os << ", ";
+    os << e;
+    i++;
+  }
+  os << "}";
+  return os;
+}
+
+template <typename T>
+ostream &operator<<(ostream &os, const unordered_set<T> &s) {
+  int i = 0;
+  os << "{";
+  for (const auto &e : s) {
+    if (i > 0)
+      os << ", ";
+    os << e;
+    i++;
+  }
+  os << "}";
+  return os;
+}
+
+void dbg() { cerr << "\n"; }
+
+template <typename T, typename... TS> void dbg(T val, TS... vals) {
+  cerr << val << " ";
+  dbg(vals...);
+}
+
+/* stuff you should look for:
+  ---------------------------
+   * special cases (n=1?)
+   * int overflow, array bounds
+   * do smth instead of nothing and stay organized
+   * WRITE STUFF DOWN
+   * DON'T GET STUCK ON ONE APPROACH
+ */
+
+void solve() {
+  int n, m;
+  cin >> n >> m;
+  vector<string> v(n);
+  for (auto &str : v) {
+    cin >> str;
+  }
+  string name = "vika";
+  int ans = 0;
+  for (int i = 0; i < m; i++) {
+    for (int j = 0; j < n; j++) {
+      if (v[j][i] == name[ans]) {
+        ans++;
+        if (ans == 4) {
+          cout << "YES\n";
+          return;
+        }
+        break;
+      }
+    }
+  }
+  cout << "NO\n";
+}
+
+int main() {
+  ios_base::sync_with_stdio(false);
+  cin.tie(NULL);
+  int tt;
+  cin >> tt;
+  while (tt--) {
+    solve();
+  }
+}
diff --git a/contests/Round894/A/main_input0.txt b/contests/Round894/A/main_input0.txt
new file mode 100644
index 0000000..0d1b190
--- /dev/null
+++ b/contests/Round894/A/main_input0.txt
@@ -0,0 +1,22 @@
+5
+1 4
+vika
+3 3
+bad
+car
+pet
+4 4
+vvvv
+iiii
+kkkk
+aaaa
+4 4
+vkak
+iiai
+avvk
+viaa
+4 7
+vbickda
+vbickda
+vbickda
+vbickda
diff --git a/contests/Round894/A/main_output0.txt b/contests/Round894/A/main_output0.txt
new file mode 100644
index 0000000..1653f37
--- /dev/null
+++ b/contests/Round894/A/main_output0.txt
@@ -0,0 +1,5 @@
+YES
+NO
+YES
+NO
+YES
diff --git a/contests/Round894/B/main b/contests/Round894/B/main
new file mode 100755
index 0000000..c215533
--- /dev/null
+++ b/contests/Round894/B/main
diff --git a/contests/Round894/B/main.cpp b/contests/Round894/B/main.cpp
new file mode 100755
index 0000000..2309503
--- /dev/null
+++ b/contests/Round894/B/main.cpp
@@ -0,0 +1,151 @@
+#include <bits/stdc++.h>
+using namespace std;
+
+using ll = long long;
+using pii = pair<int, int>;
+using vpi = vector<pii>;
+using vi = vector<int>;
+using vll = vector<long long>;
+using mpii = map<int, int>;
+using mpll = map<ll, ll>;
+using db = long double;
+
+#define pb push_back
+#define all(x) (x).begin(), (x).end()
+#define rall(x) (x).rbegin(), (x).rend()
+#define lb lower_bound
+#define ub upper_bound
+#define make_unique(x)                                                         \
+  sort(all((x)));                                                              \
+  (x).resize(unique(all((x))) - (x).begin())
+#define ceil(a, b) ((a) + (b)-1) / (b)
+
+const int MOD = (int)1e9 + 7;
+const db PI = acos((db)-1);
+const int dx[4]{1, 0, -1, 0};
+const int dy[4]{0, 1, 0, -1};
+
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const pair<K, V> &p);
+template <typename T> ostream &operator<<(ostream &os, const vector<T> &vec);
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const map<K, V> &m);
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const unordered_map<K, V> &m);
+template <typename T> ostream &operator<<(ostream &os, const set<T> &s);
+template <typename T>
+ostream &operator<<(ostream &os, const unordered_set<T> &s);
+
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const pair<K, V> &p) {
+  os << "(" << p.first << ", " << p.second << ")";
+  return os;
+}
+
+template <typename T> ostream &operator<<(ostream &os, const vector<T> &vec) {
+  os << "{";
+  for (size_t i = 0; i < vec.size(); ++i) {
+    if (i > 0)
+      os << ", ";
+    os << vec[i];
+  }
+  os << "}";
+  return os;
+}
+
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const map<K, V> &m) {
+  os << "{";
+  for (const auto &p : m) {
+    os << p.first << ": " << p.second << ", ";
+  }
+  os << "}";
+  return os;
+}
+
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const unordered_map<K, V> &m) {
+  os << "{";
+  for (const auto &p : m) {
+    os << p.first << ": " << p.second << ", ";
+  }
+  os << "}";
+  return os;
+}
+
+template <typename T> ostream &operator<<(ostream &os, const set<T> &s) {
+  int i = 0;
+  os << "{";
+  for (const auto &e : s) {
+    if (i > 0)
+      os << ", ";
+    os << e;
+    i++;
+  }
+  os << "}";
+  return os;
+}
+
+template <typename T>
+ostream &operator<<(ostream &os, const unordered_set<T> &s) {
+  int i = 0;
+  os << "{";
+  for (const auto &e : s) {
+    if (i > 0)
+      os << ", ";
+    os << e;
+    i++;
+  }
+  os << "}";
+  return os;
+}
+
+void dbg() { cerr << "\n"; }
+
+template <typename T, typename... TS> void dbg(T val, TS... vals) {
+  cerr << val << " ";
+  dbg(vals...);
+}
+
+/* stuff you should look for:
+  ---------------------------
+   * special cases (n=1?)
+   * int overflow, array bounds
+   * do smth instead of nothing and stay organized
+   * WRITE STUFF DOWN
+   * DON'T GET STUCK ON ONE APPROACH
+ */
+
+void solve() {
+  int n;
+  cin >> n;
+  vi v(n);
+  for (auto &x : v) {
+    cin >> x;
+  }
+  vi ans;
+  ans.push_back(v[0]);
+  for (int i = 1; i < n; i++) {
+    if (v[i] >= v[i - 1]) {
+      ans.push_back(v[i]);
+    } else {
+      ans.push_back(1);
+      ans.push_back(v[i]);
+    }
+  }
+  cout << ans.size() << '\n';
+  for (auto &x : ans) {
+    cout << x << ' ';
+  }
+  cout << '\n';
+}
+
+int main() {
+  ios_base::sync_with_stdio(false);
+  cin.tie(NULL);
+  int tt;
+  cin >> tt;
+  while (tt--) {
+    solve();
+  }
+}
diff --git a/contests/Round894/B/main_input0.txt b/contests/Round894/B/main_input0.txt
new file mode 100644
index 0000000..4811984
--- /dev/null
+++ b/contests/Round894/B/main_input0.txt
@@ -0,0 +1,13 @@
+6
+3
+4 6 3
+3
+1 2 3
+5
+1 7 9 5 7
+1
+144
+2
+1 1
+5
+1 2 2 1 1
diff --git a/contests/Round894/B/main_output0.txt b/contests/Round894/B/main_output0.txt
new file mode 100644
index 0000000..b2bac14
--- /dev/null
+++ b/contests/Round894/B/main_output0.txt
@@ -0,0 +1,12 @@
+6
+4 3 2 6 3 3
+3
+1 2 3
+6
+1 7 9 3 5 7
+1
+144
+2
+1 1
+6
+1 2 2 1 1 1
diff --git a/contests/Round894/C/main b/contests/Round894/C/main
new file mode 100755
index 0000000..742a347
--- /dev/null
+++ b/contests/Round894/C/main
diff --git a/contests/Round894/C/main.cpp b/contests/Round894/C/main.cpp
new file mode 100755
index 0000000..d23b5e1
--- /dev/null
+++ b/contests/Round894/C/main.cpp
@@ -0,0 +1,155 @@
+#include <algorithm>
+#include <bits/stdc++.h>
+using namespace std;
+
+using ll = long long;
+using pii = pair<int, int>;
+using vpi = vector<pii>;
+using vi = vector<int>;
+using vll = vector<long long>;
+using mpii = map<int, int>;
+using mpll = map<ll, ll>;
+using db = long double;
+
+#define pb push_back
+#define all(x) (x).begin(), (x).end()
+#define rall(x) (x).rbegin(), (x).rend()
+#define lb lower_bound
+#define ub upper_bound
+#define make_unique(x)                                                         \
+  sort(all((x)));                                                              \
+  (x).resize(unique(all((x))) - (x).begin())
+#define ceil(a, b) ((a) + (b)-1) / (b)
+
+const int MOD = (int)1e9 + 7;
+const db PI = acos((db)-1);
+const int dx[4]{1, 0, -1, 0};
+const int dy[4]{0, 1, 0, -1};
+
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const pair<K, V> &p);
+template <typename T> ostream &operator<<(ostream &os, const vector<T> &vec);
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const map<K, V> &m);
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const unordered_map<K, V> &m);
+template <typename T> ostream &operator<<(ostream &os, const set<T> &s);
+template <typename T>
+ostream &operator<<(ostream &os, const unordered_set<T> &s);
+
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const pair<K, V> &p) {
+  os << "(" << p.first << ", " << p.second << ")";
+  return os;
+}
+
+template <typename T> ostream &operator<<(ostream &os, const vector<T> &vec) {
+  os << "{";
+  for (size_t i = 0; i < vec.size(); ++i) {
+    if (i > 0)
+      os << ", ";
+    os << vec[i];
+  }
+  os << "}";
+  return os;
+}
+
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const map<K, V> &m) {
+  os << "{";
+  for (const auto &p : m) {
+    os << p.first << ": " << p.second << ", ";
+  }
+  os << "}";
+  return os;
+}
+
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const unordered_map<K, V> &m) {
+  os << "{";
+  for (const auto &p : m) {
+    os << p.first << ": " << p.second << ", ";
+  }
+  os << "}";
+  return os;
+}
+
+template <typename T> ostream &operator<<(ostream &os, const set<T> &s) {
+  int i = 0;
+  os << "{";
+  for (const auto &e : s) {
+    if (i > 0)
+      os << ", ";
+    os << e;
+    i++;
+  }
+  os << "}";
+  return os;
+}
+
+template <typename T>
+ostream &operator<<(ostream &os, const unordered_set<T> &s) {
+  int i = 0;
+  os << "{";
+  for (const auto &e : s) {
+    if (i > 0)
+      os << ", ";
+    os << e;
+    i++;
+  }
+  os << "}";
+  return os;
+}
+
+void dbg() { cerr << "\n"; }
+
+template <typename T, typename... TS> void dbg(T val, TS... vals) {
+  cerr << val << " ";
+  dbg(vals...);
+}
+
+/* stuff you should look for:
+  ---------------------------
+   * special cases (n=1?)
+   * int overflow, array bounds
+   * do smth instead of nothing and stay organized
+   * WRITE STUFF DOWN
+   * DON'T GET STUCK ON ONE APPROACH
+ */
+
+void solve() {
+  int n;
+  cin >> n;
+  vi v(n);
+  for (auto &x : v) {
+    cin >> x;
+  }
+  if (v[0] > n) {
+    cout << "NO\n";
+    return;
+  }
+  vi sorted = v;
+  vi ans;
+  sort(all(sorted));
+  ans.push_back(n);
+  for (int i = n - 2; i >= 0; i--) {
+    ans.push_back(sorted.end() - lower_bound(all(sorted), n - i));
+  }
+  for (int i = 0; i < n; i++) {
+    if (ans[i] != v[i]) {
+      cout << "NO\n";
+      return;
+    }
+  }
+  cout << "YES\n";
+}
+
+int main() {
+  ios_base::sync_with_stdio(false);
+  cin.tie(NULL);
+  int tt;
+  cin >> tt;
+  while (tt--) {
+    solve();
+  }
+}
diff --git a/contests/Round894/C/main_input0.txt b/contests/Round894/C/main_input0.txt
new file mode 100644
index 0000000..91118e5
--- /dev/null
+++ b/contests/Round894/C/main_input0.txt
@@ -0,0 +1,15 @@
+7
+5
+5 4 3 2 1
+3
+3 1 1
+3
+4 2 1
+1
+2
+5
+5 3 3 1 1
+5
+5 5 5 3 3
+2
+6 1
diff --git a/contests/Round894/C/main_output0.txt b/contests/Round894/C/main_output0.txt
new file mode 100644
index 0000000..4699a2d
--- /dev/null
+++ b/contests/Round894/C/main_output0.txt
@@ -0,0 +1,7 @@
+YES
+YES
+NO
+NO
+YES
+YES
+NO
diff --git a/contests/Round894/D/main b/contests/Round894/D/main
new file mode 100755
index 0000000..96b21d9
--- /dev/null
+++ b/contests/Round894/D/main
diff --git a/contests/Round894/D/main.cpp b/contests/Round894/D/main.cpp
new file mode 100755
index 0000000..f0890a4
--- /dev/null
+++ b/contests/Round894/D/main.cpp
@@ -0,0 +1,149 @@
+#include <bits/stdc++.h>
+using namespace std;
+
+using ll = long long;
+using pii = pair<int, int>;
+using vpi = vector<pii>;
+using vi = vector<int>;
+using vll = vector<long long>;
+using mpii = map<int, int>;
+using mpll = map<ll, ll>;
+using db = long double;
+
+#define pb push_back
+#define all(x) (x).begin(), (x).end()
+#define rall(x) (x).rbegin(), (x).rend()
+#define lb lower_bound
+#define ub upper_bound
+#define make_unique(x)                                                         \
+  sort(all((x)));                                                              \
+  (x).resize(unique(all((x))) - (x).begin())
+#define ceil(a, b) ((a) + (b)-1) / (b)
+
+const int MOD = (int)1e9 + 7;
+const db PI = acos((db)-1);
+const int dx[4]{1, 0, -1, 0};
+const int dy[4]{0, 1, 0, -1};
+
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const pair<K, V> &p);
+template <typename T> ostream &operator<<(ostream &os, const vector<T> &vec);
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const map<K, V> &m);
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const unordered_map<K, V> &m);
+template <typename T> ostream &operator<<(ostream &os, const set<T> &s);
+template <typename T>
+ostream &operator<<(ostream &os, const unordered_set<T> &s);
+
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const pair<K, V> &p) {
+  os << "(" << p.first << ", " << p.second << ")";
+  return os;
+}
+
+template <typename T> ostream &operator<<(ostream &os, const vector<T> &vec) {
+  os << "{";
+  for (size_t i = 0; i < vec.size(); ++i) {
+    if (i > 0)
+      os << ", ";
+    os << vec[i];
+  }
+  os << "}";
+  return os;
+}
+
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const map<K, V> &m) {
+  os << "{";
+  for (const auto &p : m) {
+    os << p.first << ": " << p.second << ", ";
+  }
+  os << "}";
+  return os;
+}
+
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const unordered_map<K, V> &m) {
+  os << "{";
+  for (const auto &p : m) {
+    os << p.first << ": " << p.second << ", ";
+  }
+  os << "}";
+  return os;
+}
+
+template <typename T> ostream &operator<<(ostream &os, const set<T> &s) {
+  int i = 0;
+  os << "{";
+  for (const auto &e : s) {
+    if (i > 0)
+      os << ", ";
+    os << e;
+    i++;
+  }
+  os << "}";
+  return os;
+}
+
+template <typename T>
+ostream &operator<<(ostream &os, const unordered_set<T> &s) {
+  int i = 0;
+  os << "{";
+  for (const auto &e : s) {
+    if (i > 0)
+      os << ", ";
+    os << e;
+    i++;
+  }
+  os << "}";
+  return os;
+}
+
+void dbg() { cerr << "\n"; }
+
+template <typename T, typename... TS> void dbg(T val, TS... vals) {
+  cerr << val << " ";
+  dbg(vals...);
+}
+
+/* stuff you should look for:
+  ---------------------------
+   * special cases (n=1?)
+   * int overflow, array bounds
+   * do smth instead of nothing and stay organized
+   * WRITE STUFF DOWN
+   * DON'T GET STUCK ON ONE APPROACH
+ */
+
+bool isValid(ll n, ll x) { return n * (n + 1) / 2 <= x; }
+
+ll sum(ll x) { return x * (x + 1) / 2; }
+
+ll binarySearch(ll x) {
+  ll left = 0, right = INT_MAX;
+  while (left < right) {
+    ll mid = left + (right - left) / 2;
+    if (isValid(mid, x))
+      left = mid + 1;
+    else
+      right = mid;
+  }
+  return left - 1;
+}
+void solve() {
+  ll x;
+  cin >> x;
+  ll bs = binarySearch(x);
+  cout << x - sum(bs) + bs + 1 << '\n';
+}
+
+int main() {
+  ios_base::sync_with_stdio(false);
+  cin.tie(NULL);
+  int tt;
+  cin >> tt;
+  while (tt--) {
+    solve();
+  }
+}
diff --git a/contests/Round894/D/main_input0.txt b/contests/Round894/D/main_input0.txt
new file mode 100644
index 0000000..f7b049a
--- /dev/null
+++ b/contests/Round894/D/main_input0.txt
@@ -0,0 +1,6 @@
+5
+1
+3
+6
+179
+1000000000000000000
diff --git a/contests/Round894/D/main_output0.txt b/contests/Round894/D/main_output0.txt
new file mode 100644
index 0000000..98bdd7a
--- /dev/null
+++ b/contests/Round894/D/main_output0.txt
@@ -0,0 +1,5 @@
+2
+3
+4
+27
+2648956421
diff --git a/contests/Round894/E/main.cpp b/contests/Round894/E/main.cpp
new file mode 100755
index 0000000..82c5879
--- /dev/null
+++ b/contests/Round894/E/main.cpp
@@ -0,0 +1,129 @@
+#include <bits/stdc++.h>
+using namespace std;
+
+using ll = long long;
+using pii = pair<int, int>;
+using vpi = vector<pii>;
+using vi = vector<int>;
+using vll = vector<long long>;
+using mpii = map<int, int>;
+using mpll = map<ll, ll>;
+using db = long double;
+
+#define pb push_back
+#define all(x) (x).begin(), (x).end()
+#define rall(x) (x).rbegin(), (x).rend()
+#define lb lower_bound
+#define ub upper_bound
+#define make_unique(x)                                                         \
+  sort(all((x)));                                                              \
+  (x).resize(unique(all((x))) - (x).begin())
+#define ceil(a, b) ((a) + (b)-1) / (b)
+
+const int MOD = (int)1e9 + 7;
+const db PI = acos((db)-1);
+const int dx[4]{1, 0, -1, 0};
+const int dy[4]{0, 1, 0, -1};
+
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const pair<K, V> &p);
+template <typename T> ostream &operator<<(ostream &os, const vector<T> &vec);
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const map<K, V> &m);
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const unordered_map<K, V> &m);
+template <typename T> ostream &operator<<(ostream &os, const set<T> &s);
+template <typename T>
+ostream &operator<<(ostream &os, const unordered_set<T> &s);
+
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const pair<K, V> &p) {
+  os << "(" << p.first << ", " << p.second << ")";
+  return os;
+}
+
+template <typename T> ostream &operator<<(ostream &os, const vector<T> &vec) {
+  os << "{";
+  for (size_t i = 0; i < vec.size(); ++i) {
+    if (i > 0)
+      os << ", ";
+    os << vec[i];
+  }
+  os << "}";
+  return os;
+}
+
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const map<K, V> &m) {
+  os << "{";
+  for (const auto &p : m) {
+    os << p.first << ": " << p.second << ", ";
+  }
+  os << "}";
+  return os;
+}
+
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const unordered_map<K, V> &m) {
+  os << "{";
+  for (const auto &p : m) {
+    os << p.first << ": " << p.second << ", ";
+  }
+  os << "}";
+  return os;
+}
+
+template <typename T> ostream &operator<<(ostream &os, const set<T> &s) {
+  int i = 0;
+  os << "{";
+  for (const auto &e : s) {
+    if (i > 0)
+      os << ", ";
+    os << e;
+    i++;
+  }
+  os << "}";
+  return os;
+}
+
+template <typename T>
+ostream &operator<<(ostream &os, const unordered_set<T> &s) {
+  int i = 0;
+  os << "{";
+  for (const auto &e : s) {
+    if (i > 0)
+      os << ", ";
+    os << e;
+    i++;
+  }
+  os << "}";
+  return os;
+}
+
+void dbg() { cerr << "\n"; }
+
+template <typename T, typename... TS> void dbg(T val, TS... vals) {
+  cerr << val << " ";
+  dbg(vals...);
+}
+
+/* stuff you should look for:
+  ---------------------------
+   * special cases (n=1?)
+   * int overflow, array bounds
+   * do smth instead of nothing and stay organized
+   * WRITE STUFF DOWN
+   * DON'T GET STUCK ON ONE APPROACH
+ */
+
+void solve() { <()> }
+
+int main() {
+  ios_base::sync_with_stdio(false);
+  cin.tie(NULL);
+  int tt;
+  cin >> tt;
+  while (tt--) {
+    solve();
+  }
+}
diff --git a/contests/Round894/F/main.cpp b/contests/Round894/F/main.cpp
new file mode 100755
index 0000000..82c5879
--- /dev/null
+++ b/contests/Round894/F/main.cpp
@@ -0,0 +1,129 @@
+#include <bits/stdc++.h>
+using namespace std;
+
+using ll = long long;
+using pii = pair<int, int>;
+using vpi = vector<pii>;
+using vi = vector<int>;
+using vll = vector<long long>;
+using mpii = map<int, int>;
+using mpll = map<ll, ll>;
+using db = long double;
+
+#define pb push_back
+#define all(x) (x).begin(), (x).end()
+#define rall(x) (x).rbegin(), (x).rend()
+#define lb lower_bound
+#define ub upper_bound
+#define make_unique(x)                                                         \
+  sort(all((x)));                                                              \
+  (x).resize(unique(all((x))) - (x).begin())
+#define ceil(a, b) ((a) + (b)-1) / (b)
+
+const int MOD = (int)1e9 + 7;
+const db PI = acos((db)-1);
+const int dx[4]{1, 0, -1, 0};
+const int dy[4]{0, 1, 0, -1};
+
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const pair<K, V> &p);
+template <typename T> ostream &operator<<(ostream &os, const vector<T> &vec);
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const map<K, V> &m);
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const unordered_map<K, V> &m);
+template <typename T> ostream &operator<<(ostream &os, const set<T> &s);
+template <typename T>
+ostream &operator<<(ostream &os, const unordered_set<T> &s);
+
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const pair<K, V> &p) {
+  os << "(" << p.first << ", " << p.second << ")";
+  return os;
+}
+
+template <typename T> ostream &operator<<(ostream &os, const vector<T> &vec) {
+  os << "{";
+  for (size_t i = 0; i < vec.size(); ++i) {
+    if (i > 0)
+      os << ", ";
+    os << vec[i];
+  }
+  os << "}";
+  return os;
+}
+
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const map<K, V> &m) {
+  os << "{";
+  for (const auto &p : m) {
+    os << p.first << ": " << p.second << ", ";
+  }
+  os << "}";
+  return os;
+}
+
+template <typename K, typename V>
+ostream &operator<<(ostream &os, const unordered_map<K, V> &m) {
+  os << "{";
+  for (const auto &p : m) {
+    os << p.first << ": " << p.second << ", ";
+  }
+  os << "}";
+  return os;
+}
+
+template <typename T> ostream &operator<<(ostream &os, const set<T> &s) {
+  int i = 0;
+  os << "{";
+  for (const auto &e : s) {
+    if (i > 0)
+      os << ", ";
+    os << e;
+    i++;
+  }
+  os << "}";
+  return os;
+}
+
+template <typename T>
+ostream &operator<<(ostream &os, const unordered_set<T> &s) {
+  int i = 0;
+  os << "{";
+  for (const auto &e : s) {
+    if (i > 0)
+      os << ", ";
+    os << e;
+    i++;
+  }
+  os << "}";
+  return os;
+}
+
+void dbg() { cerr << "\n"; }
+
+template <typename T, typename... TS> void dbg(T val, TS... vals) {
+  cerr << val << " ";
+  dbg(vals...);
+}
+
+/* stuff you should look for:
+  ---------------------------
+   * special cases (n=1?)
+   * int overflow, array bounds
+   * do smth instead of nothing and stay organized
+   * WRITE STUFF DOWN
+   * DON'T GET STUCK ON ONE APPROACH
+ */
+
+void solve() { <()> }
+
+int main() {
+  ios_base::sync_with_stdio(false);
+  cin.tie(NULL);
+  int tt;
+  cin >> tt;
+  while (tt--) {
+    solve();
+  }
+}