feat(codeforces): 855

codeforces/855/1800e2.cc

@@ -0,0 +1,95 @@
+#include <bits/stdc++.h> // {{{
+
+#include <version>
+#ifdef __cpp_lib_ranges_enumerate
+#include <ranges>
+namespace rv = std::views;
+namespace rs = std::ranges;
+#endif
+
+// https://codeforces.com/blog/entry/96344
+
+#pragma GCC optimize("O2,unroll-loops")
+#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
+
+using namespace std;
+
+using i16 = int16_t;
+using u16 = uint16_t;
+using i32 = int32_t;
+using u32 = uint32_t;
+using i64 = int64_t;
+using u64 = uint64_t;
+using f64 = double;
+using f128 = long double;
+
+#if __cplusplus >= 202002L
+template <typename T> constexpr T MIN = std::numeric_limits<T>::min();
+
+template <typename T> constexpr T MAX = std::numeric_limits<T>::max();
+#endif
+
+#ifdef LOCAL
+#define db(...) std::print(__VA_ARGS__)
+#define dbln(...) std::println(__VA_ARGS__)
+#else
+#define db(...)
+#define dbln(...)
+#endif
+//  }}}
+
+bitset<2 * 100000> seen;
+void solve() {
+  seen.reset();
+  u32 n, k;
+  cin >> n >> k;
+  string s, t;
+  cin >> s >> t;
+
+  u32 ans = 0;
+  vector<u32> f(26, 0);
+
+  auto dfs = [&](auto &&self, i32 i) -> void {
+    if (i < 0 || i >= n || seen[i])
+      return;
+    seen[i] = true;
+    ++f[s[i] - 'a'];
+    --f[t[i] - 'a'];
+    for (auto d : {i - k, i - k - 1, i + k, i + k + 1}) {
+      self(self, d);
+    }
+  };
+
+  bool ok = true;
+  for (i32 i = 0; i < n && ok; ++i) {
+    if (!seen[i]) {
+      dfs(dfs, i);
+      ok &= count(f.begin(), f.end(), 0) == 26;
+      f.assign(26, 0);
+    }
+  }
+
+  cout << (ok ? "YES" : "NO") << '\n';
+}
+
+int main() { // {{{
+  std::cin.exceptions(std::cin.failbit);
+
+#ifdef LOCAL
+  std::cerr.rdbuf(std::cout.rdbuf());
+  std::cout.setf(std::ios::unitbuf);
+  std::cerr.setf(std::ios::unitbuf);
+#else
+  std::cin.tie(nullptr)->sync_with_stdio(false);
+#endif
+
+  u32 tc = 1;
+  std::cin >> tc;
+
+  for (u32 t = 0; t < tc; ++t) {
+    solve();
+  }
+
+  return 0;
+}
+// }}}