#include <stdio.h>

int main(){
    int cup, N, i;
    int P, Q;

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

    return 0;
}