package main

import (
	"fmt"
)

func main() {
	var n, m int
	fmt.Scan(&n, &m)
	var p, q int
	for i := 0; i < m; i++ {
		fmt.Scan(&p, &q)
		if p == n {
			n = q
		} else if q == n {
			n = p
		}
	}
	fmt.Println(n)
}