#include <iostream>
#include <vector>
#include <unordered_map>

using namespace std;

int main() {
    vector<int> nums = {1, 2, 3, 2, 4, 1, 2};

    unordered_map<int, int> freq;

    for (int num : nums) {
        freq[num]++;
    }

    cout << "Repeated elements:\n";
    for (auto &entry : freq) {
        if (entry.second > 1) {
            cout << entry.first << " appears " << entry.second << " times\n";
        }
    }

    return 0;
}