#include <cstdio>
#include <cstdlib>
#include <iostream>
#include <string>
#include <cmath>
#include <algorithm>
#include <vector>
#include <queue>
#include <stack>
#include <map>
#include <set>
#include <cstring>

typedef long long ll;
using namespace std;

#define mod 1000003
#define INF 1000000000
#define LLINF 2000000000000000000LL

#define SIZE 10000

int main(){
    int n,m,p,q;
    
    scanf("%d%d",&n,&m);
    
    for(int i=0;i<m;i++){
        scanf("%d%d",&p,&q);
        
        if(p==n) n=q;
        else if(q==n) n=p;
    }
    
    printf("%d\n",n);
    
}