#include<stdio.h>
long long nr[100010],sum;
long long solutie(long long k,long long n){
	if(sum/k>=nr[n-1])
		return sum/k;
	sum-=nr[n-1];
	return solutie(k-1,n-1);
}
int main(){
	freopen("grupuri.in","r",stdin);
	freopen("grupuri.out","w",stdout);
	long long n,k,i;
	scanf("%lld%lld",&k,&n);
	for(i=0;i<n;++i){
		scanf("%lld",&nr[i]);
		sum+=nr[i];
	}
	printf("%lld\n",solutie(k,n));
	fclose(stdin);
	fclose(stdout);
	return 0;
}