#include <iostream>

using namespace std;

const int MAX_N = 5 * 1e3;
const int MAX_G = 1e5;

int n, g_max, dp[MAX_N + 1][MAX_G + 1];

struct object {
	int profit;
	int greutate;
}v[MAX_N + 1];

int main() {

	cin >> n >> g_max;

	for (int i = 1; i <= n; i++)
		cin >> v[i].profit >> v[i].greutate;

	for (int i = 1; i <= n; i++) {
		for (int j = 1; j <= g_max; j++) {
			object curr_object = v[i];

			cout << curr_object.greutate;
		}
	}

	return 0;
}