#include<stdio.h>
FILE*fin,*fout;
long long n,k,a,i,j,s,u,p,max,m;
int main(){
fin=fopen("grupuri.in","r");
fout=fopen("grupuri.out","w");
fscanf(fin,"%lld %lld",&k,&n);
for(i=1;i<=n;i++){
fscanf(fin,"%lld",&a);
s=s+a;
}
p=1;u=s/k;
while(p<=u){
m=(u+p)/2;

if(m*k>s){

u=m-1;
}
else{
if(m>max){max=m;}
p=m+1;
}
}
fprintf(fout,"%lld",max);
return 0;}