#include<stdio.h>


int main(void){

int N,M,A[51]={},a,i,j,temp=0;

	scanf("%d %d",&N,&M);

for(i=1;i<=N;i++){
	A[i]=i;
}



for(j=1;j<=M;j++){
	scanf("%d",&a);
	temp=A[a];

	for(i=a;i>1;i--){
		A[i]=A[i-1];
	}
	A[1]=temp;
			//for(i=1;i<=N;i++){途中経過
			//printf("A[%d]=%d\n",i,A[i]);
			//}
}

printf("%d\n",A[1]);

return 0;



}