package main

import "fmt"

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