Counting ones

In file included from /usr/include/c++/13/iostream:41,
                 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:25:29:
/usr/include/c++/13/ostream:204:25: warning: 'b1' may be used uninitialized [-Wmaybe-uninitialized]
  204 |       { return _M_insert(__n); }
      |                ~~~~~~~~~^~~~~
input/code.cpp: In function 'int main()':
input/code.cpp:13:15: note: 'b1' was declared here
   13 |     long long b1, b2, best=0;
      |               ^~
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:25:42:
/usr/include/c++/13/ostream:204:25: warning: 'b2' may be used uninitialize...

#include <iostream>
#include <vector>

using namespace std;

int main(){
    long long n;
    cin >> n;
    vector<long long> arr(n);
    for (long long i=0;i<n;i++){
        cin >> arr[i];
    }
    long long b1, b2, best=0;
    for (long long i=0;i<n;i++){
        for (long long j=i+1;j<n;j++){
            long long prod=arr[i]*arr[j];
            long long cnt=__builtin_popcountll(prod);
            if (cnt>best){
                best=cnt;
                b1=arr[i];
                b2=arr[j];
            }
        }
    }
    cout << best << '\n' << b1 << ' ' << b2 << '\n';
    return 0;
}

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