#include <stdio.h>
#include <stdlib.h>

int main(void)
{
	int n, m, *p, *q;
	scanf("%d", &n);
	scanf("%d", &m);
	p = malloc(sizeof(int)*m);
	q = malloc(sizeof(int)*m);
	for (int i = 0; i < m; i++) {
		scanf("%d%d", &p[i], &q[i]);
		if (p[i] == n) n = q[i];
		else if (q[i] == n) n = p[i];
	}
	printf("%d\n", n);
	return 0;
}