Submission #80582

#	Time	Username	Problem	Language	Result	Execution time	Memory
80582		inom	Birthday gift (IZhO18_treearray)	C++14	56 / 100	4094 ms	53160 KiB

treearray

#include <bits/stdc++.h>
 
#define fi first
#define se second
#define pb push_back
#define sz(c) (int)(c).size()
#define all(c) (c).begin(), (c).end()
#define in freopen("input.txt", "r", stdin);
#define out freopen("output.txt", "w", stdout);

using namespace std;
  
const int N = 2 * 1e5 + 10;
const int MOD = 1e9 + 7;
const int INF = 1e9;

int TN = 1;

int n, m, Q, l = 1;
vector<int> verr[N], up[N];
int tin[N], tout[N], timer, node[N];

void dfs(int x, int pr = 1) {
    tin[x] = ++timer;
    up[x][0] = pr;
    for (int i = 1; i <= l; i++) {
        up[x][i] = up[up[x][i - 1]][i - 1];
    }
    for (auto i: verr[x]) {
        if (i != pr) {
            dfs(i, x);
        }
    }
    tout[x] = ++timer;
}

bool upper(int a, int b) {
    return tin[a] <= tin[b] && tout[a] >= tout[b];
}

int lca(int a, int b) {
    if (upper(a, b)) {
        return a;
    }
    else if (upper(b, a)) {
        return b;
    }
    for (int i = l; i >= 0; i--) {
        if (!upper(up[a][i], b)) {
            a = up[a][i];
        }
    }
    return up[a][0];
}

void solve() {
    cin >> n >> m >> Q;
    for (int i = 1; i < n; i++) {
        int x, y;
        cin >> x >> y;
        verr[x].pb(y); verr[y].pb(x);
    }
    while ((1<<l) <= n) {
        l++;
    }
    for (int i = 1; i <= n; i++) {
        up[i].resize(l + 10);
    
    }
    dfs(1);
    for (int i = 1; i <= m; i++) {
        cin >> node[i];
    }
    while (Q--) {
        int type;
        cin >> type;
        if (type == 1) {
            int pos, v;
            cin >> pos >> v;
            node[pos] = v;
        }
        else {
            int l, r, v;
            cin >> l >> r >> v;
            bool ok = false;
            for (int i = l; i <= r; i++) {
                if (node[i] == v) {
                    cout << i << " " << i << "\n"; ok = true; break;
                }
            }
            if (ok) {
                continue;
            }
            ok = false;
            for (int i = l; i < r; i++) {
                if (lca(node[i], node[i + 1]) == v) {
                    cout << i << " " << i + 1 << "\n"; ok = true; break;
                }
            }
            if (!ok) {
                cout << -1 << " " << -1 << "\n";
            }
        }
    }
    return;
}

signed main() {
    // ios_base::sync_with_stdio(0);
    // in; out; 
    // cin >> TN;
    while (TN--) solve();
    return 0;
 }

• Subtask 1: 12 / 12
• Subtask 2: 18 / 18
• Subtask 3: 26 / 26
• Subtask 4: 0 / 44