#include <stdio.h>
#include <stdlib.h>
int main()
{
  int N;
  int M;
  int *P;
  int *Q;
  scanf("%d", &N);
  scanf("%d", &M);
  P = (int*)malloc(sizeof(int)*M);
  Q = (int*)malloc(sizeof(int)*M);
  int i;
  for (i=0; i<M; i++) {
    scanf("%d", &(P[i]));
    scanf("%d", &(Q[i]));
  }
  for (i=0; i<M; i++) {
    if (N == P[i]) {
      N = Q[i];
    } else if (N == Q[i]) {
      N = P[i];
    }
  }
  printf("%d\n", N);
  return 0;
}