| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 435547 | Collypso | Counting Mushrooms (IOI20_mushrooms) | C++17 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
#define ll long long
#define ld long double
#define pii pair<int, int>
#define pll pair<ll, ll>
#define vt vector
#define pb push_back
#define all(x) (x).begin(), (x).end()
#define sz(x) (int) (x).size()
#pragma GCC optimize ("O3")
#pragma GCC optimize ("O2")
#define F first
#define S second
//#define endl '\n'
//#define int long long
using namespace std;
int use_machine(vt<int> x);
int subtask1(int n)
{
int ans = 1;
for(int i = 1; i < n - 1; i += 2)
{
int tmp = use_machine({i + 1, 0, i});
if (tmp == 0) ans += 2;
else if (tmp == 1) ans += 1;
}
if (n % 2 == 0) ans += !use_machine({0, n - 1});
return ans;
}
//if (n <= 452) return subtask1(n);
int count_mushrooms(int n)
{
vt<int> v[2];
v[0].pb(0);
int q = 1, ans = 1, attempts = min(400, sqrt(n));
while(q < n && attempts--)
{
if (use_machine({0, q}) == 0) v[0].pb(q), ans++;
else v[1].pb(q);
q++;
}
int r = (sz(v[1]) > sz(v[0])) ? 1 : 0;
int X = sz(v[r]);
if (q >= n) return ans;
for(int i = 0, to = (n - q + X - 2) / (X - 1); i < to; i++)
{
vt<int> tmp(1, v[r][0]);
for(int j = 1; q < n && j < X; q++, j++)
tmp.pb(q), tmp.pb(v[r][j]);
if (r == 1) ans += use_machine(tmp) / 2;
else ans += sz(tmp) / 2 - use_machine(tmp) / 2;
//cout << ans << endl;
//for(int x : tmp) cout << x << " ";
//cout << endl;
//cout << use_machine(tmp) << endl;
}
return ans;
}