Equilateral numbers

#include <bits/stdc++.h>
#include <limits>
using namespace std;
typedef long long ll;


int main()
{

    ll n;
    cin >> n;
    vector<ll> dp;

    ll k = 1;
    ll eq = 1;
    dp.push_back(k);
    ++k;
    //cout << eq << endl;
    while (eq <= n)
    {
        eq += k;
        dp.push_back(eq);
        ++k;
        //cout << eq << endl;
    }

    ll i = dp.size() - 1;
    ll max = n;

    ll nops = 0;
    while (max > 0 and i >= 0)
    {

        if (dp[i] <= max)
        {
            //cout << "->>>" << dp[i] << endl;
            max -= dp[i];
            ++nops;
        }
        else
            --i;
    }

    cout << nops << endl;
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: WRONG ANSWER

Test 6

Verdict: WRONG ANSWER

Test 7

Verdict: WRONG ANSWER

Test 8

Verdict: WRONG ANSWER

Test 9

Verdict: WRONG ANSWER

Test 10

Verdict: ACCEPTED

Test 11

Verdict: WRONG ANSWER

Test 12

Verdict: WRONG ANSWER