Block_Problem.cpp

# include   <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef vector<ll> vl;
# define    endl                '\n'
# define    fi                  first
# define    se                  second
# define    all(a)              a.begin(), a.end()
ll cost(ll k, ll n, vl& a)
{
    vl temp;
    for (ll i = 0; i < n; i++)
    {
        ll tempcost = a[i] + (k * (i + 1));
        temp.push_back(tempcost);
    }
    sort(all(temp));
    ll count = 0;
    for (ll i = 0; i < k; i++)
    {
        count += temp[i];
    }
    return count;
}
int main()
{
    ll n, i, s; cin >> n >> s;
    vl a(n);
    for (i = 0; i < n; i++) cin >> a[i];
    ll l = 0, r = n;
    ll ansk = -1, ans2;
    while (l <= r)
        //l<r  ->in any case
        //l<=r ->mid+1,mid-1
    {
        ll k = l + (r - l) / 2;//(l+r)/2
        //k fixed here by binary search
        ll count = cost(k, n, a);
        if (count > s)
        {
            r = (k - 1);
            continue;
        }
        if (count <= s)
        {
            if (k > ansk)
            {
                ansk = k, ans2 = count;
            }
            l = k + 1;
            continue;
        }
    }
    cout << ansk << " " << ans2 << " " << endl;
    return 0;
}