import java.util.Scanner;

/**
 * No.26 シャッフルゲーム
 */
public class No026_ShuffleGame {

	public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int a = sc.nextInt();	// 初期位置
        int b = sc.nextInt();	// 入力列数
        String[] cup = new String[]{"","×","×","×"};
		cup[a] = "〇";
        
        for (int i=0; i<b; i++) {
            int c = sc.nextInt();	// 入れ替え位置左
            int d = sc.nextInt();	// 入れ替え位置右
            String tmp = "";
            tmp = cup[c];
            cup[c] = cup[d];
            cup[d] = tmp;
        }
        
        for (int i=1; i< cup.length; i++) {
        	if ("〇".equals(cup[i])) {
        		System.out.println(i);
        		break;
        	}
        }
	}

}