import sys

def detect_duplicates(album_lines):
    # 哈希表：id -> [出现次数, 时间戳]
    mp = {}

    for line in album_lines:
        arr = list(map(int, line.strip().split()))
        # 每行是 2M 个数字，按 (id, ts) 成对读取
        for i in range(0, len(arr), 2):
            pid = arr[i]
            ts = arr[i + 1]
            if pid not in mp:
                mp[pid] = [1, ts]
            else:
                mp[pid][0] += 1

    res = []
    for pid, (cnt, ts) in mp.items():
        if cnt > 1:
            res.append((ts, pid, cnt))

    # 按时间戳升序；时间戳相同用 id 升序兜底
    res.sort()

    # 组织输出为 id count id count ...
    out = []
    for _, pid, cnt in res:
        out.append(str(pid))
        out.append(str(cnt))
    return " ".join(out)

def main():
    data = sys.stdin.read().splitlines()
    if not data:
        return
    n = int(data[0].strip())
    album_lines = data[1:1 + n]
    ans = detect_duplicates(album_lines)
    sys.stdout.write(ans)

if __name__ == "__main__":
    main()

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

// 题面功能：检测跨相册重复图片，返回 (id, count) 序列字符串
string detectDuplicates(const vector<string>& albumLines) {
    // 哈希表：id -> {count, timestamp}
    unordered_map<int, pair<int,int>> mp;

    for (const string& line : albumLines) {
        stringstream ss(line);
        int id, ts;
        // 每行按 (id, ts) 成对读取
        while (ss >> id >> ts) {
            auto it = mp.find(id);
            if (it == mp.end()) {
                mp[id] = {1, ts};
            } else {
                it->second.first += 1; // 出现次数加一
            }
        }
    }

    // 收集重复项：{ts, id, count}
    vector<tuple<int,int,int>> vec;
    for (auto &kv : mp) {
        int id = kv.first;
        int cnt = kv.second.first;
        int ts = kv.second.second;
        if (cnt > 1) vec.push_back(make_tuple(ts, id, cnt));
    }

    // 按时间戳升序；相同时间戳按 id 升序
    sort(vec.begin(), vec.end(), [](const auto& a, const auto& b){
        if (get<0>(a) != get<0>(b)) return get<0>(a) < get<0>(b);
        return get<1>(a) < get<1>(b);
    });

    // 组织输出
    stringstream out;
    for (int i = 0; i < (int)vec.size(); i++) {
        if (i) out << ' ';
        out << get<1>(vec[i]) << ' ' << get<2>(vec[i]); // 输出 id count
    }
    return out.str();
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int N;
    cin >> N;
    string dummy;
    getline(cin, dummy); // 吃掉行尾换行

    vector<string> albumLines;
    albumLines.reserve(N);
    for (int i = 0; i < N; i++) {
        string line;
        getline(cin, line);
        albumLines.push_back(line);
    }

    cout << detectDuplicates(albumLines);
    return 0;
}

import java.io.*;
import java.util.*;

public class Main {

    // 题面功能：检测跨相册重复图片，返回输出字符串
    static String detectDuplicates(List<String> albumLines) {
        // 哈希表：id -> [count, timestamp]
        HashMap<Integer, int[]> map = new HashMap<Integer, int[]>();

        for (String line : albumLines) {
            line = line.trim();
            if (line.length() == 0) continue;
            String[] parts = line.split("\\s+");
            // 每行是 (id, ts) 成对出现
            for (int i = 0; i < parts.length; i += 2) {
                int id = Integer.parseInt(parts[i]);
                int ts = Integer.parseInt(parts[i + 1]);
                int[] val = map.get(id);
                if (val == null) {
                    map.put(id, new int[]{1, ts});
                } else {
                    val[0] += 1; // 出现次数加一
                }
            }
        }

        // 收集重复项：用数组保存 [ts, id, count]
        ArrayList<int[]> list = new ArrayList<int[]>();
        for (Map.Entry<Integer, int[]> e : map.entrySet()) {
            int id = e.getKey();
            int cnt = e.getValue()[0];
            int ts = e.getValue()[1];
            if (cnt > 1) {
                list.add(new int[]{ts, id, cnt});
            }
        }

        // 按时间戳升序；相同时间戳按 id 升序
        Collections.sort(list, new Comparator<int[]>() {
            public int compare(int[] a, int[] b) {
                if (a[0] != b[0]) return a[0] - b[0];
                return a[1] - b[1];
            }
        });

        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < list.size(); i++) {
            int[] x = list.get(i);
            if (sb.length() > 0) sb.append(' ');
            sb.append(x[1]).append(' ').append(x[2]); // 输出 id count
        }
        return sb.toString();
    }

    public static void main(String[] args) throws Exception {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        String first = br.readLine();
        if (first == null || first.trim().length() == 0) return;
        int n = Integer.parseInt(first.trim());

        List<String> albumLines = new ArrayList<String>();
        for (int i = 0; i < n; i++) {
            albumLines.add(br.readLine());
        }

        String ans = detectDuplicates(albumLines);
        System.out.print(ans);
    }
}