#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; using ll = long long; template auto range(T s, T e) { return views::iota(s, max(s, e)); } template auto range(T n) { return range(0, n); } template void take(vector& vec, int n) { vec.resize(n); for (int i = 0; i < n; ++i) cin >> vec[i]; } template void sout(const Args &...args) { ((cout << args << ' '), ...); } template void soutn(const Args &...args) { ((cout << args << ' '), ...); cout << '\n'; } template struct In2 { T1 a; T2 b; friend std::istream& operator>>(std::istream& is, In2& obj) { T1 t1; T2 t2; is >> t1 >> t2; obj = {t1, t2}; return is; } }; template struct In3 { T1 a; T2 b; T3 c; friend std::istream& operator>>(std::istream& is, In3& obj) { T1 t1; T2 t2; T3 t3; is >> t1 >> t2 >> t3; obj = {t1, t2, t3}; return is; } }; template struct In4 { T1 a; T2 b; T3 c; T4 d; friend std::istream& operator>>(std::istream& is, In4& obj) { T1 t1; T2 t2; T3 t3; T4 t4; is >> t1 >> t2 >> t3 >> t4; obj = {t1, t2, t3, t4}; return is; } }; #ifdef LOCAL #include #else #define dump(...) ; #endif namespace { int n; vector va; void read() { cin >> n; take(va, n); } /* string run() { for (int i : range(n - 1)) { swap(va[i], va[i + 1]); for (int j : range(n - 1)) if (va[j] == va[j + 1]) return "Yes"; swap(va[i], va[i + 1]); } return "No"; } */ string run() { for (int i : range(n - 1)) { if (va[i - 1] == va[i + 1]) return "Yes"; if (va[i] == va[i + 2]) return "Yes"; } return "No"; } } // namespace template void exec(F f) { if constexpr (std::is_same_v) f(); else cout << f() << endl; } int main(int argc, char** argv) { cerr << fixed << setprecision(12); cout << fixed << setprecision(12); int testcase = 1; if (argc > 1) testcase = atoi(argv[1]); while (testcase--) { read(); } exec(run); }