Submission #366669

#	Time	Username	Problem	Language	Result	Execution time	Memory
366669		534351	Safety (NOI18_safety)	C++17	100 / 100	68 ms	5556 KiB

safety

#include <bits/stdc++.h>

using namespace std;

template<class T, class U>
void ckmin(T &a, U b)
{
    if (a > b) a = b;
}

template<class T, class U>
void ckmax(T &a, U b)
{
    if (a < b) a = b;
}

#define MP make_pair
#define PB push_back
#define LB lower_bound
#define UB upper_bound
#define fi first
#define se second
#define SZ(x) ((int) (x).size())
#define ALL(x) (x).begin(), (x).end()
#define FOR(i, a, b) for (auto i = (a); i < (b); i++)
#define FORD(i, a, b) for (auto i = (a) - 1; i >= (b); i--)

typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<pii> vpi;
typedef vector<pll> vpl;

int N;
ll H;
priority_queue<ll> lt;
priority_queue<ll, vector<ll>, greater<ll> > rt;
ll ans;

int32_t main()
{
    cout << fixed << setprecision(12);
    cerr << fixed << setprecision(4);
    ios_base::sync_with_stdio(false); cin.tie(0);
    cin >> N >> H;
    //so each # in lt actually means x - i * H
    //so each # in rt actually means x + i * H
    FOR(i, 0, N)
    {
        ll v;
        cin >> v;
        if (i == 0)
        {
            lt.push(v);
            rt.push(v);
            continue;
        }
        ll lv = lt.top() - i * H, rv = rt.top() + i * H;
        // cerr << lv << ' ' << rv << endl;
        if (v < lv)
        {
            lt.pop();
            lt.push(v + i * H);
            lt.push(v + i * H);
            rt.push(lv - i * H);
            //the cost at lv just increased by
            ans += (lv - v);
        }
        else if (v > rv)
        {
            rt.pop();
            rt.push(v - i * H);
            rt.push(v - i * H);
            lt.push(rv + i * H);
            //the cost at rv just increased by
            // cerr << rt.top() + i * H << ',' << lt.top() - i * H << endl;
            ans += (v - rv);
        }
        else
        {
            lt.push(v + i * H);
            rt.push(v - i * H);
        }
    }
    cout << ans << '\n';
    return 0;
}

• Subtask 1: 3 / 3
• Subtask 2: 4 / 4
• Subtask 3: 9 / 9
• Subtask 4: 5 / 5
• Subtask 5: 6 / 6
• Subtask 6: 11 / 11
• Subtask 7: 11 / 11
• Subtask 8: 22 / 22
• Subtask 9: 29 / 29