Counting ones

In file included from /usr/include/c++/13/bits/unique_ptr.h:42,
                 from /usr/include/c++/13/memory:78,
                 from /usr/include/x86_64-linux-gnu/c++/13/bits/stdc++.h:56,
                 from input/code.cpp:1:
In member function 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(long long int) [with _CharT = char; _Traits = std::char_traits<char>]',
    inlined from 'int main()' at input/code.cpp:17:28:
/usr/include/c++/13/ostream:204:25: warning: 'x' may be used uninitialized [-Wmaybe-uninitialized]
  204 |       { return _M_insert(__n); }
      |                ~~~~~~~~~^~~~~
input/code.cpp: In function 'int main()':
input/code.cpp:10:15: note: 'x' was declared here
   10 |     long long x, y;
      |               ^
In member function 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(long long int) [with _CharT = char; _Traits = std::char_traits<char>]',...

#include <bits/stdc++.h>
using namespace std;

int main() {
    int n, ans = 0;
    cin >> n;
    vector<long long> a(n);
    for (auto &x : a) cin >> x;

    long long x, y;
    for (int i = 0; i < n; i++)
        for (int j = i + 1; j < n; j++) {
            int b = __builtin_popcountll(a[i] * a[j]);
            if (b > ans) ans = b, x = a[i], y = a[j];
        }

    cout << ans << '\n' << x << ' ' << y << '\n';
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED