#include<stdio.h>

int main(void)
{
	int i, k, mo[4] = {0,0,0,0}, a[2], t, ans, m;

	scanf("%d %d", &ans, &m);
	for (i = 0; i < m; i++) {
		scanf("%d %d", &a[0], &a[1]);
			if (ans == a[0]) ans = a[1];
			else if(ans == a[1])ans = a[0];
	}
	printf("%d", ans);

	return 0;
}