Submission #1044050

#	Time	Username	Problem	Language	Result	Execution time	Memory
1044050		SamAnd	Text editor (CEOI24_editor)	C++17	100 / 100	1447 ms	111016 KiB

Main

#include <bits/stdc++.h>
using namespace std;
#define m_p make_pair
#define all(x) (x).begin(),(x).end()
#define sz(x) ((int)(x).size())
#define fi first
#define se second
typedef long long ll;
mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());
mt19937 rnf(2106);
const int N = 1000006;
const ll INF = 1000000009000000009;

int n;
int x1, y1_;
int x2, y2;
int a[N];
int ul[N], ur[N];

struct ban
{
    int x, z;
    ll d;
    ban(){}
    ban(int x, int z, ll d)
    {
        this->x = x;
        this->z = z;
        this->d = d;
    }
};

bool operator<(const ban& a, const ban& b)
{
    return (a.d > b.d);
}

bool c[N][2];
ll d[N][2];
priority_queue<ban> q;
void djk()
{
    for (int x = 1; x <= n; ++x)
        for (int z = 0; z < 2; ++z)
            d[x][z] = INF;
    while (1)
    {
        ban t;
        do
        {
            if (q.empty())
                return;
            t = q.top();
            q.pop();
        } while (c[t.x][t.z]);
        c[t.x][t.z] = true;
        d[t.x][t.z] = t.d;

        if (t.z == 0)
        {
            {
                ban h = t;
                if (h.x > 1)
                {
                    --h.x;
                    ++h.d;
                    q.push(h);
                }
            }
            {
                ban h = t;
                if (h.x < n)
                {
                    ++h.x;
                    ++h.d;
                    q.push(h);
                }
            }
            {
                ban h = t;
                if (h.x > 1)
                {
                    --h.x;
                    h.z = 1;
                    ++h.d;
                    q.push(h);
                }
            }
        }
        else
        {
            {
                ban h = t;
                if (ul[t.x] >= 1)
                {
                    h.d += abs(t.x - ul[t.x]);
                    h.x = ul[t.x];
                    q.push(h);
                }
            }
            {
                ban h = t;
                if (ur[t.x] <= n)
                {
                    h.d += abs(t.x - ur[t.x]);
                    h.x = ur[t.x];
                    q.push(h);
                }
            }
            {
                ban h = t;
                if (h.x < n)
                {
                    ++h.x;
                    h.z = 0;
                    ++h.d;
                    q.push(h);
                }
            }
        }
        ban h = t;
        h.d += (a[t.x] - 1);
        h.z ^= 1;
        q.push(h);
    }
}

void solv()
{
    cin >> n;
    cin >> x1 >> y1_;
    cin >> x2 >> y2;
    for (int i = 1; i <= n; ++i)
    {
        cin >> a[i];
        ++a[i];
    }

    stack<int> s;
    for (int i = 1; i <= n; ++i)
    {
        while (!s.empty() && a[i] <= a[s.top()])
            s.pop();
        if (s.empty())
            ul[i] = 0;
        else
            ul[i] = s.top();
        s.push(i);
    }
    while (!s.empty())
        s.pop();
    for (int i = n; i >= 1; --i)
    {
        while (!s.empty() && a[i] <= a[s.top()])
            s.pop();
        if (s.empty())
            ur[i] = n + 1;
        else
            ur[i] = s.top();
        s.push(i);
    }

    ll ans = INF;
    for (int x = x1; x <= n; ++x)
    {
        if (a[x] < y1_)
        {
            q.push(ban(x, 1, abs(x1 - x)));
            break;
        }
        q.push(ban(x, 0, abs(x1 - x) + abs(y1_ - 1)));
        q.push(ban(x, 1, abs(x1 - x) + abs(y1_ - a[x])));
        if (x == x2)
            ans = min(ans, abs(x1 - x2) + 0LL + abs(y1_ - y2));
    }
    for (int x = x1; x >= 1; --x)
    {
        if (a[x] < y1_)
        {
            q.push(ban(x, 1, abs(x1 - x)));
            break;
        }
        q.push(ban(x, 0, abs(x1 - x) + abs(y1_ - 1)));
        q.push(ban(x, 1, abs(x1 - x) + abs(y1_ - a[x])));
        if (x == x2)
            ans = min(ans, abs(x1 - x2) + 0LL + abs(y1_ - y2));
    }

    djk();

    for (int x = 1; x <= n; ++x)
    {
        ans = min(ans, d[x][0] + abs(x - x2) + abs(1 - y2));
        if (ul[x] < x2 && x2 < ur[x])
            ans = min(ans, d[x][1] + abs(x - x2) + abs(a[x] - y2));
    }

    cout << ans << "\n";
}

int main()
{
    #ifdef SOMETHING
    freopen("input.txt", "r", stdin);
    //freopen("output.txt", "w", stdout);
    #endif // SOMETHING
    ios_base::sync_with_stdio(false), cin.tie(0);

    int tt = 1;
    //cin >> tt;
    while (tt--)
    {
        solv();
    }
    return 0;
}

• Subtask 0: 0 / 0
• Subtask 1: 5 / 5
• Subtask 2: 14 / 14
• Subtask 3: 26 / 26
• Subtask 4: 11 / 11
• Subtask 5: 44 / 44