2023 rcpc

2023/rcpc/d2/editorial/j-parallelogram-38.cpp

@@ -0,0 +1,45 @@
+#include <iostream>
+#include <vector>
+#include <algorithm>
+#include <cassert>
+#warning That's the baby, that's not my baby
+
+typedef long long ll;
+
+void solve() {
+  int n;
+  std::cin >> n;
+  int f[n] = {};
+  for (int i = 0; i < n; i++) {
+    int x;
+    std::cin >> x;
+    --x;
+    f[x]++;
+  }
+  int gr4 = 0, gr2 = 0;
+  for (int i = 0; i < n; i++) {
+    if (f[i] >= 4) {
+      gr4++;
+    } else if (f[i] >= 2) {
+      gr2++;
+    }
+  }
+  if (gr4 > 0 || gr2 >= 2) {
+    std::cout << "YES\n";
+  } else {
+    std::cout << "NO\n";
+  }
+}
+
+int main() {
+  std::ios_base::sync_with_stdio(false);
+  std::cin.tie(0);
+
+  int t;
+  std::cin >> t;
+  while (t--) {
+    solve();
+  }
+
+  return 0;
+}