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#include <iostream>
#include <vector>

using namespace std;

/**
	Helpful links
	lcm https://www.geeksforgeeks.org/program-to-find-lcm-of-two-numbers/
*/

void display(const vector<int>& v)
{
	for (int i = 0; i < v.size(); ++i)
		printf("%d ", v[i]);
	printf("\n");
}

// Recursive function to return gcd of a and b
long long gcd(long long int a, long long int b)
{
	if (b == 0)
		return a;
	return gcd(b, a % b);
}

// Function to return LCM of two numbers
long long lcm(int a, int b)
{
	return (a / gcd(a, b)) * b;
}

int main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);

	int n, r, l;

	cin >> n;

	vector<bool> visited_platforms(n+1);
	int nww = 1;

	visited_platforms[1] = true;
	for (int i = 1; i <= n; i++)
	{
		cin >> r;

		bool is_current_visited = visited_platforms[i];
		if (is_current_visited)
		{
			if (r == 0)
			{
				continue;
			}
			nww = lcm(nww, r);
		}

		for (int j = 0; j < r; j++)
		{
			cin >> l;

			if (is_current_visited)
			{
				visited_platforms[l] = true;
			}
		}
	}

	cout << nww;
}