#include <iostream>
using namespace std;
long long nums[int(1e6+10)];
long long n,m;
bool check(long long mid){
    long long sum = 0;
    for(int i = 1;i<=n;i++)
    {
        if(nums[i]>mid) 
            sum+=nums[i]-mid;
    }
    if(sum>=m) 
        return true;
    else 
        return false;
}    
int main(){
    long long l = 0,r = 0,mid;
    cin>>n>>m;
    for(int i = 1;i<=n;i++)
    {
        cin>>nums[i];
        if(nums[i]>r)
            r = nums[i];
    }
    while(l<r){
        mid = (l+r)/2;
        if(check(mid))
            l = mid+1;
        else 
            r = mid-1;
    }    
    cout<<mid;
    return 0;
}