#include <stdio.h>

int main()
{
	int n, m;
	scanf("%d%d", &n, &m);

	for (int i = 0; i < m; i++)
	{
		int p, q;
		scanf("%d%d", &p, &q);

		if (p == n)
		{
			n = q;
		}
		else if (q == n)
		{
			n = p;
		}
	}

	printf("%d", n);

	return 0;
}