package main

import "fmt"

func main() {
    var n, m int
    fmt.Scan(&n, &m)

    for i := 0; i < m; i++ {
        var p, q int
        fmt.Scan(&p, &q)

        if n == p {
            n = q
        } else if n == q {
            n = p
        }
    }

    fmt.Println(n)
}