include<bits/stdc++.h>

using namespace std;

define ll long long

ll i,j,n,m,a[1000001],t=0,d=0;
int main()
{
cin>>n>>m;
for(i=1;i<=m;i++){cin>>a[i];t+=a[i];}
while(t%n!=0)
{
t--;
d++;
}
if(d>0&&d<=n)cout<<t/n+1;

}