#include <bits/stdc++.h>
using namespace std;
#define int              long long int
#define double           long double
#define print(a)         for(auto x : a) cout << x << " "; cout << endl


const int M = 1000000007;
const int N = 3e5+9;
const int INF = 2e9+1;
const int LINF = 2000000000000000001;

inline int power(int a, int b, int mod=M) {
    int x = 1;
    a %= mod;
    while (b) {
        if (b & 1) x = (x * a) % mod; 
        a = (a * a) % mod;
        b >>= 1;
    }
    return x;
}


//_ ***************************** START Below *******************************




vector<vector<int>> a;

vector<int> consistency(int n){
    //* {next minimum,  row, col}
    priority_queue<vector<int>, vector<vector<int>>, greater<vector<int>> > minHp;
    int maxi = INT32_MIN;
    for(int i=0; i<n; i++){
        maxi = max(maxi, a[i][0]);
        minHp.push({a[i][0], i, 0});
    }
    int s = -1;
    int e = -1;
    int dist = INT32_MAX;
    while(!minHp.empty()){
        auto top = minHp.top();
        minHp.pop();
        int mini = top[0];
        int r = top[1];
        int c = top[2];
        if(maxi-mini < dist){
            dist = maxi - mini;
            s = mini;
            e = maxi;
        }
        if(c+1 < a[r].size()) {
            maxi = max(maxi, a[r][c+1]);
            minHp.push({a[r][c+1], r, c+1});
        }
        else break;
        
    }
    
    return {s, e};
}















vector<int> practice(int n){



}





void solve() {
    
    int n;
    cin>> n;
    
    a.resize(n);
    for(int i=0; i<n; i++){
    	int m;
    	cin >> m;
		for(int j=0; j<m; j++) {
			int x;
			cin >> x;
			a[i].push_back(x);
		}
    }
    
    auto ans = consistency(n);
    
    cout << ans[0] << " " << ans[1] << endl;


}





int32_t main() {
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

    int t = 1;
    // cin >> t;
    while (t--) {
        solve();
    }

    return 0;
}