#include <stdio.h>
#include <string.h>

int main(void){
    int i, j, N, M;
    scanf("%d %d", &N, &M);

    int P, Q;
    for(i=0;i<M;i++){
        scanf("%d %d", &P, &Q);
        if(N==P){
            N = Q;
        }else if(N==Q){
            N = P;
        }
    }
    printf("%d\n", N);
    return 0;
}