#include // {{{ #include #ifdef __cpp_lib_ranges_enumerate #include 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 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 constexpr T MIN = std::numeric_limits::min(); template constexpr T MAX = std::numeric_limits::max(); template [[nodiscard]] static T sc(auto&& x) { return static_cast(x); } template [[nodiscard]] static T sz(auto&& x) { return static_cast(x.size()); } #endif static void NO() { std::cout << "NO\n"; } static void YES() { std::cout << "YES\n"; } template using vec = std::vector; #define all(x) (x).begin(), (x).end() #define rall(x) (x).rbegin(), (x).rend() #define ff first #define ss second #ifdef LOCAL #define db(...) std::print(__VA_ARGS__) #define dbln(...) std::println(__VA_ARGS__) #else #define db(...) #define dbln(...) #endif // }}} bitset<100000 + 1> friends; void solve() { /* binary search on alpha how to know if i can choose at least n - 1 shops to give each guy a present basically, choose, out of all m shops, n shops, one gives each guy a present (in the worst) hm - must dynamically, per bsearch query, filter arrays consider each array: if someone unset can be set, + 1 to count, update max if already set, take max of large value challenge: n - 1 shops, not all n take a step back: we have m arrays, each which set values offriend individually consider each friend separately - have multiple values of joy set to; filter to >= mid alphaq not nec. choose ones that set most -> greedy ok - one shop per friend - per friend, iterate - find shop that sets their joy >= alpha now, either < n (bad) or n shops - consider each friend as the "substitute" candidate in other words, consider each friend, and iter AGAIN thru the shit - can we find ANOTHER diff array setting this guy, as well as setting another friend? if so, done! */ u32 m, n; cin >> m >> n; vec> p(m, vec(n)); u64 maxp = 0; for (auto& row : p) { for (auto& e : row) { cin >> e; maxp = max(maxp, e); } } u64 l = 1, r = maxp; auto ok = [&](u64 alpha) { friends.reset(); bool both_covered = false; for (auto& shop : p) { u32 shop_count = 0; for (u32 i = 0; i < n; ++i) { if (shop[i] >= alpha) { ++shop_count; friends.set(i); } } both_covered |= shop_count > 1; } return friends.count() == n && both_covered; }; while (l <= r) { u64 alpha = l + (r - l) / 2; if (ok(alpha)) { l = alpha + 1; } else { r = alpha - 1; } } println("{}", r); } 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; } // }}}