#include<stdio.h>
main(){
    int N,M;
    scanf("%d%d",&N,&M);
    int num = N;
    for(int i = 0;i < M;i++){
        int a,b;
        scanf("%d%d",&a,&b);
        if(a == num){
            num = b;
        }else if(b == num){
            num = a;
        }
    }
    printf("%d\n",num);
}