Counting ones

#include <iostream>
#include <vector>
#include <bitset>
#include <utility>

using namespace std;

// Function to count the number of 1 bits in the binary representation of a number
int countBits(int num) {
    return bitset<32>(num).count();
}

int main() {
    int n;
    cin >> n;
    vector<int> a(n);

    // Reading the array elements
    for (int i = 0; i < n; ++i) {
        cin >> a[i];
    }

    int maxBits = 0;
    pair<int, int> bestPair = {a[0], a[1]};

    // Loop to find the pair with maximum 1-bits in product
    for (int i = 0; i < n; ++i) {
        for (int j = i + 1; j < n; ++j) {
            int product = a[i] * a[j];
            int bits = countBits(product);

            // Update if this product has more 1 bits
            if (bits > maxBits) {
                maxBits = bits;
                bestPair = {a[i], a[j]};
            }
        }
    }

    // Output the results
    cout << maxBits << endl;
    cout << bestPair.first << " " << bestPair.second << endl;

    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: WRONG ANSWER

Test 7

Verdict: WRONG ANSWER

Test 8

Verdict: WRONG ANSWER

Test 9

Verdict: WRONG ANSWER

Test 10

Verdict: WRONG ANSWER