cp/codeforces/928/d.cc
2025-08-24 14:47:38 -05:00

95 lines
1.6 KiB
C++

#include <bits/stdc++.h> // {{{
// 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 <typename T>
constexpr T MIN = std::numeric_limits<T>::min();
template <typename T>
constexpr T MAX = std::numeric_limits<T>::max();
template <typename T>
[[nodiscard]] static T sc(auto&& x) {
return static_cast<T>(x);
}
template <typename T>
[[nodiscard]] static T sz(auto&& x) {
return static_cast<T>(x.size());
}
#endif
static void NO() {
std::cout << "NO\n";
}
static void YES() {
std::cout << "YES\n";
}
template <typename T>
using vec = std::vector<T>;
#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
// }}}
void solve() {
u32 n;
cin >> n;
vec<u32> a(n);
for (auto& e : a)
cin >> e;
multiset<u32> seen;
u32 ans = 0;
for (auto e : a) {
auto complement = ((1LL << 31) - 1) ^ e;
if (seen.empty() || !seen.contains(complement)) {
seen.insert(e);
} else {
seen.erase(seen.find(complement));
++ans;
}
}
println("{}", ans + seen.size());
}
int main() { // {{{
cin.tie(nullptr)->sync_with_stdio(false);
cin.exceptions(cin.failbit);
u32 tc = 1;
cin >> tc;
for (u32 t = 0; t < tc; ++t) {
solve();
}
return 0;
}
// }}}