Submission #1261380

#	Time	Username	Problem	Language	Result	Execution time	Memory
1261380		tvgk	Port Facility (JOI17_port_facility)	C++20	100 / 100	920 ms	186464 KiB

port_facility

#include<bits/stdc++.h>
using namespace std;
#define task "a"
#define se second
#define fi first
#define ll long long
#define ii pair<ll, ll>
const long mxN = 2e6 + 7, MOD = 1e9 + 7;

ii lazy[mxN * 4], tree[mxN * 4], dsu[mxN], a[mxN];
int n;

void Down(int j)
{
    if (!lazy[j].fi)
        return;

    if (tree[j * 2].fi)
    {
        tree[j * 2] = lazy[j];
        lazy[j * 2] = lazy[j];
    }
    if (tree[j * 2 + 1].fi)
    {
        tree[j * 2 + 1] = lazy[j];
        lazy[j * 2 + 1] = lazy[j];
    }

    lazy[j] = {0, 0};
}

void Up(int j)
{
    if (!tree[j * 2].fi)
        tree[j] = tree[j * 2 + 1];
    else if (!tree[j * 2 + 1].fi)
        tree[j] = tree[j * 2];
    else if (tree[j * 2] != tree[j * 2 + 1])
        tree[j].fi = -1;
    else
        tree[j] = tree[j * 2];
}

ii Find(int j)
{
    if (dsu[j].fi != j)
    {
        ii res = Find(dsu[j].fi);
        dsu[j].fi = res.fi;
        dsu[j].se ^= res.se;
    }
    return dsu[j];
}

void Union(ii u, ii v)
{
    bool tmp = u.se;
    u = Find(u.fi);

    if (u.fi == v.fi)
    {
        if ((u.se ^ tmp) == v.se)
        {
            cout << 0;
            exit(0);
        }
        return;
    }

    dsu[u.fi].fi = v.fi;
    dsu[u.fi].se = u.se ^ 1 ^ tmp;
    return;
}

void Get(int u, int v, int id, int j = 1, int l = 1, int r = n * 2)
{
    if (u > r || l > v || !tree[j].fi)
        return;

    if (u <= l && r <= v && tree[j].fi != -1)
    {
        Union(tree[j], {id, 0});
        tree[j] = lazy[j] = {id, 1};
        return;
    }
    Down(j);

    int mid = (l + r) / 2;
    Get(u, v, id, j * 2, l, mid);
    Get(u, v, id, j * 2 + 1, mid + 1, r);
    Up(j);
}

void Upd(int vt, int id, int j = 1, int l = 1, int r = n * 2)
{
    if (vt > r || l > vt)
        return;

    if (l == r)
    {
        tree[j] = {id, 0};
        return;
    }
    Down(j);

    int mid = (l + r) / 2;
    Upd(vt, id, j * 2, l, mid);
    Upd(vt, id, j * 2 + 1, mid + 1, r);
    Up(j);
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    //freopen(task".INP", "r", stdin);
    //freopen(task".OUT", "w", stdout);

    cin >> n;
    for (int i = 1; i <= n; i++)
    {
        cin >> a[i].fi >> a[i].se;
        dsu[i].fi = i;
        dsu[i].se = 0;
    }
    sort(a + 1, a + n + 1);

    for (int i = 1; i <= n; i++)
    {
        //cout << i << " : " << a[i].fi << " " << a[i].se << '\n';
        Get(a[i].fi, a[i].se, i);
        Upd(a[i].se, i);
    }

    ll ans = 1;
    for (int i = 1; i <= n; i++)
    {
        if (Find(i).fi == i)
            ans = ans * 2 % MOD;
    }
    cout << ans;
}

• Subtask 1: 10 / 10
• Subtask 2: 12 / 12
• Subtask 3: 56 / 56
• Subtask 4: 22 / 22