#include<bits/stdc++.h>
#define int long long
using namespace std;
const int maxn = 1e6 + 5;
int n, k;
int a[maxn];
int ans;
inline bool check(int x)
{
int res = 0;
for(int i = 1; i <= n; i++)
res += max(0ll, x - a[i] + 1ll);
return res <= x * k;
}
signed main()
{
cin >> n >> k;
for(int i = 1; i <= n; i++)
cin >> a[i];
int l = 0, r = 1e18;
while(l <= r)
{
int mid = (l + r) >> 1;
if(check(mid))
{
ans = mid;
l = mid + 1;
}
else
r = mid - 1;
}
cout << ans;
return 0;
}