Submission #492350

#	Time	Username	Problem	Language	Result	Execution time	Memory
492350		Rainbowbunny	Birthday gift (IZhO18_treearray)	C++17	100 / 100	958 ms	84680 KiB

treearray

#include <bits/stdc++.h>
using namespace std;

const int MAXN = 2e5 + 5;
const int MAXL = 20;

int n, m, q;
int up[MAXN][MAXL], a[MAXN], H[MAXN];
vector <int> Adj[MAXN];

set <int> Pos[MAXN];
set <int> Nex[MAXN];

void DFS(int node, int p = 1)
{
    up[node][0] = p;
    for(int i = 1; i < MAXL; i++)
    {
        up[node][i] = up[up[node][i - 1]][i - 1];
    }
    for(auto x : Adj[node])
    {
        if(x == p)
        {
            continue;
        }
        H[x] = H[node] + 1;
        DFS(x, node);
    }
}

int LCA(int u, int v)
{
    if(H[u] < H[v])
    {
        swap(u, v);
    }
    int tmp = H[u] - H[v];
    for(int i = MAXL - 1; i >= 0; i--)
    {
        if(tmp & (1 << i))
        {
            u = up[u][i];
        }
    }
    if(u == v)
    {
        return u;
    }
    for(int i = MAXL - 1; i >= 0; i--)
    {
        if(up[u][i] != up[v][i])
        {
            u = up[u][i];
            v = up[v][i];
        }
    }
    return up[u][0];
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    cin >> n >> m >> q;
    for(int i = 1; i < n; i++)
    {
        int u, v;
        cin >> u >> v;
        Adj[u].push_back(v);
        Adj[v].push_back(u);
    }
    DFS(1);
    for(int i = 1; i <= m; i++)
    {
        cin >> a[i];
        Pos[a[i]].insert(i);
        if(i != 1)
        {
            Nex[LCA(a[i - 1], a[i])].insert(i - 1);
        }
    }
    while(q--)
    {
        int Type;
        cin >> Type;
        if(Type == 1)
        {
            int pos, v;
            cin >> pos >> v;
            Pos[a[pos]].erase(pos);
            Pos[v].insert(pos);
            if(pos > 1)
            {
                Nex[LCA(a[pos - 1], a[pos])].erase(pos - 1);
                Nex[LCA(a[pos - 1], v)].insert(pos - 1);
            }
            if(pos < m)
            {
                Nex[LCA(a[pos], a[pos + 1])].erase(pos);
                Nex[LCA(a[pos + 1], v)].insert(pos);
            }
            a[pos] = v;
        }
        else
        {
            int l, r, v;
            cin >> l >> r >> v;
            set <int> :: iterator it;
            it = Pos[v].lower_bound(l);
            if(it != Pos[v].end() and *it <= r)
            {
                cout << *it << ' ' << *it << '\n';
                continue;
            }
            it = Nex[v].lower_bound(l);
            if(it != Nex[v].end() and *it < r)
            {
                cout << *it << ' ' << *it + 1 << '\n';
                continue;
            }
            cout << -1 << ' ' << -1 << '\n';
        }
    }
}

• Subtask 1: 12 / 12
• Subtask 2: 18 / 18
• Subtask 3: 26 / 26
• Subtask 4: 44 / 44