#include <iostream> #include <vector> #include <unordered_map> using namespace std; bool canAvoidTantrum(const vector<int>& fruits) { unordered_map<int, int> lastDay; for (int i = 0; i < fruits.size(); ++i) { if (lastDay.find(fruits[i]) != lastDay.end() && lastDay[fruits[i]] == i - 1) { return false; } lastDay[fruits[i]] = i; } return true; } int main() { int k; cin >> k; for (int t = 0; t < k; ++t) { int n; cin >> n; vector<int> fruits(n); for (int i = 0; i < n; ++i) { cin >> fruits[i]; } if (canAvoidTantrum(fruits)) { cout << "Y" << endl; } else { cout << "N" << endl; } } return 0; }