Counting ones

input/code.cpp: In function 'int main()':
input/code.cpp:37:37: warning: 'a' may be used uninitialized [-Wmaybe-uninitialized]
   37 |         cout << max << "\n" << a << " " << b;
      |                                     ^~~
input/code.cpp:24:20: note: 'a' was declared here
   24 |         int count, a, b, max;
      |                    ^
input/code.cpp:37:44: warning: 'b' may be used uninitialized [-Wmaybe-uninitialized]
   37 |         cout << max << "\n" << a << " " << b;
      |                                            ^
input/code.cpp:24:23: note: 'b' was declared here
   24 |         int count, a, b, max;
      |                       ^

#include <bits/stdc++.h>
#include <vector>
using namespace std;
#define rep(i, a, b) for(int i = a; i < (b); ++i)
#define all(x) begin(x), end(x)
#define sz(x) (int)(x).size()
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;

int main() {
        cin.tie(0)->sync_with_stdio(0);
        cin.exceptions(cin.failbit);
        vector<ll> arr;
        int n;
        cin >> n;

        ll x;
        rep(i, 0, n) {
          cin >> x;
          arr.push_back(x);
        }

        int count, a, b, max;
        max = 0;
        rep(i, 0, n) {
          rep(j, i, n) {
            x = arr[i] * arr[j];
            count = __builtin_popcountll(x);
            if (count > max) {
              max = count;
              a = arr[i];
              b = arr[j];
            }
          }
        }
        cout << max << "\n" << a << " " << b;

}

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