#include<cstdio>
long long v[100005],k,n;
long long check(int x){
long long i,rez=0;
for(i=1;i<=n;i++)
if (v[i]<x)
rez=rez+v[i];
else
rez=rez+x;
if (rez>=k*x)
return 1;
return 0;}
int main(){
freopen("grupuri.in","r",stdin);
freopen("grupuri.out","w",stdout);
long long i,s=0,st,dr,mij,last;
scanf("%lld%lld",&k,&n);
for(i=1;i<=n;i++)
scanf("%lld",&v[i]),s=s+v[i];
st=0;
dr=s/k;
while(st<=dr){
mij=(st+dr)/2;
if (check(mij)){
last=mij;
st=mij+1;}
else
dr=mij-1;}
printf("%lld\n",last);
return 0;}