Submission #495710

#	Time	Username	Problem	Language	Result	Execution time	Memory
495710		kingline	Birthday gift (IZhO18_treearray)	C++17	30 / 100	4078 ms	5724 KiB

treearray

#include <bits/stdc++.h>
#define pb push_back
#define ios ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define all(data) data.begin() , data.end()
#define endl '\n'
//freopen("nenokku_easy.in", "r", stdin);
//freopen("nenokku_easy.out", "w", stdout);
#define int long long
#define pii pair < int, int >

using namespace std;

typedef long long ll;
const int N = 2e5 + 5;
int lg;

int n, m, q, tin[N], tout[N], sz, up[N][20], a[N];
vector < int > g[N];

void dfs(int v, int pr) {
    tin[v] = ++sz;
    up[v][0] = pr;
    for(int i = 1; i < lg; i++) {
        up[v][i] = up[up[v][i - 1]][i - 1];
    }
    for(int i = 0; i < g[v].size(); i++) {
        int to = g[v][i];
        if(to != pr) {
            dfs(to, v);
        }
    }
    tout[v] = ++sz;
}

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

int lca(int x, int y) {
    if(upper(x, y)) return x;
    if(upper(y, x)) return y;
    for(int i = lg - 1; i >= 0; i--) {
        if(up[x][i] == 0) continue;
        if(!upper(up[x][i], y)) {
            x = up[x][i];
        }
    }
    return up[x][0];
}

main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    cin >> n >> m >> q;
    while((1 << lg) <= n) {
        lg++;
    }
    for(int i = 1; i < n; i++) {
        int a, b;
        cin >> a >> b;
        g[a].pb(b);
        g[b].pb(a);
    }
    dfs(1, 1);
    for(int i = 1; i <= m; i++) {
        cin >> a[i];
    }
    while(q--) {
        int tp, pos, l, r, v;
        cin >> tp;
        if(tp % 2) {
            cin >> pos >> v;
            a[pos] = v;
        } else {
            cin >> l >> r >> v;
            bool ok = 0;
            for(int i = l; i <= r; i++) {
                int lc = a[i];
                if(lc == v) {
                    cout << i << " " << i << endl;
                    ok = 1;
                    break;
                }
                for(int j = i + 1; j <= r; j++) {
                    lc = lca(lc, a[j]);
                    if(lc == v) {
                        ok = 1;
                        cout << i << " " << j << endl;
                        break;
                    }
                }
                if(ok) break;
            }
            if(!ok) cout << "-1 -1\n";
        }
    }
}

Compilation message (stderr)

treearray.cpp: In function 'void dfs(long long int, long long int)':
treearray.cpp:26:22: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   26 |     for(int i = 0; i < g[v].size(); i++) {
      |                    ~~^~~~~~~~~~~~~
treearray.cpp: At global scope:
treearray.cpp:51:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   51 | main() {
      | ^~~~

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