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#include <algorithm>
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using pii = pair<int, int>;
using vpii = vector<pii>;
using vi = vector<int>;
using vll = vector<long long>;
using mpii = map<int, int>;
using mpll = map<ll, ll>;
using db = long double;
#define pb push_back
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define lb lower_bound
#define ub upper_bound
#define make_unique(x) \
sort(all((x))); \
(x).resize(unique(all((x))) - (x).begin())
#define ceil(a, b) ((a) + (b)-1) / (b)
const int mod = (int)1e9 + 7;
const db pi = acos((db)-1);
const int dx[4]{1, 0, -1, 0};
const int dy[4]{0, 1, 0, -1};
#ifdef LOCAL
#include "debug.h"
#else
#define dbg(...) 42
#endif
/* stuff you should look for:
---------------------------
* special cases (n=1?)
* int overflow, array bounds
* do smth instead of nothing and stay organized
* WRITE STUFF DOWN
* DON'T GET STUCK ON ONE APPROACH
*/
int binarySearch(const std::vector<int> &arr, int target) {
int left = 0;
int right = arr.size() - 1;
while (left <= right) {
int mid = left + (right - left) / 2;
if (arr[mid] == target) {
return mid;
} else if (arr[mid] < target) {
left = mid + 1;
} else {
right = mid - 1;
}
}
return -1;
}
int negateNumber(int num) {
int signMask = 1 << (sizeof(int) * 8 - 1);
int inverted = ~num & (signMask - 1);
return inverted + 1;
}
void solve() {
random_device rd;
mt19937 gen(rd());
uniform_int_distribution<> distribution(1, INT_MAX);
int n;
cin >> n;
vi v(n);
for (auto &x : v) {
cin >> x;
}
sort(all(v));
int ans = 0;
vector<bool> marked(n, false);
for (int i = 0; i < n; i++) {
auto it = binarySearch(v, negateNumber(v[i]) - 1);
if (it != -1) {
ans++;
v[it] = distribution(gen);
marked[i] = true;
marked[it] = true;
}
}
int cnt = count(all(marked), false);
cout << ans + cnt << '\n';
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(NULL);
int tt;
cin >> tt;
while (tt--) {
solve();
}
}
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