Submission #1215481

#	Time	Username	Problem	Language	Result	Execution time	Memory
1215481		vanea	Tree (IOI24_tree)	C++20	0 / 100	2093 ms	33468 KiB

tree

#include <bits/stdc++.h>
#include "tree.h"
using namespace std;
using ll = long long;

const int mxN = 2e5+10;
const int INF = 1e9+10;

bool one;
vector<int> adj[mxN];
int n, timer = -1, l, r, leaves = 0;
int tin[mxN], tout[mxN], sz[mxN];
ll ans = 0, w[mxN], cnt[mxN], first = 0;
array<int, 2> st[4*mxN];

void dfs(int node, int p) {
    tin[node] = ++timer;
    bool leaf = true;
    for(auto it : adj[node]) {
        if(it == p) continue;
        leaf = false;
        dfs(it, node);
        sz[node] += sz[it];
    }
    if(!leaf) first += sz[node];
    leaves += leaf;
    sz[node] += leaf;
    tout[node] = timer;
}

void build(int node, int l, int r) {
    if(l == r) {
        st[node] = {INF, 0};
        return ;
    }
    int mid = (l+r)/2;
    build(node*2, l, mid); build(node*2+1, mid+1, r);
    st[node] = min(st[node*2], st[node*2+1]);
}

void upd(int node, int l, int r, int k, array<int, 2> x) {
    if(l == r && l == k) {
        st[node] = x;
        return ;
    }
    if(l > k || r < k) return ;
    int mid = (l+r)/2;
    upd(node*2, l, mid, k, x);
    upd(node*2+1, mid+1, r, k, x);
    st[node] = min(st[node*2], st[node*2+1]);
}

array<int, 3> qry(int node, int l, int r, int l1, int r1) {
    if(l1 <= l && r <= r1) {
        array<int, 3> now = {st[node][0], st[node][1], l};
        return now;
    }
    if(l1 > r || r1 < l) return {INF, 0, 0};
    int mid = (l+r)/2;
    return min(qry(node*2, l, mid, l1, r1), qry(node*2+1, mid+1, r, l1, r1));
}

void dfs1(int node, int p) {
    bool leaf = true;
    for(auto it : adj[node]) {
        if(it == p) continue;
        leaf = false;
        dfs1(it, node);
        cnt[node] += cnt[it];
    }
    if(leaf) {
        ans += l*w[node];
        cnt[node] = l;
        return ;
    }
    while(cnt[node] > r) {
        array<int, 3> now = qry(1, 0, timer+1, tin[node], tout[node]);
        if(now[0] >= w[node]) {
            ans += (cnt[node] - r) * w[node];
            cnt[node] = r;
            break;
        }
        int nxt = cnt[node] - now[1];
        if(nxt <= r) {
            nxt = (cnt[node]-r); cnt[node] -= nxt;
            now[1] -= nxt; ans += now[0] * nxt;
            upd(1, 0, timer+1, now[2], {now[0], now[1]});
        }
        else {
            cnt[node] -= now[1]; ans += now[0] * now[1];
            upd(1, 0, timer+1, now[2], {INF, 0});
        }
    }
    upd(1, 0, timer+1, tin[node], {w[node], r-l});
}

void init(vector<int> P, vector<int> W) {
    n = P.size();
    one = true;
    for(int i = 0; i < n; i++) {
        w[i] = W[i];
        if(w[i] != 1) one = false;
    }
    for(int i = 1; i < n; i++) {
        adj[P[i]].push_back(i);
    }
    dfs(0, -1);
}

ll query(int L, int R) {
    ans = 0; l = L; r = R;
    if(one) {
        ans = max(0LL, first * L - (R * (n - leaves)));
        ans += L * leaves;
    }
    else {
        build(1, 0, timer+1);
        for(int i = 0; i < n; i++) cnt[i] = 0;
        dfs1(0, -1);
    }
    return ans;
}

/*int main()
{
    init({-1, 0, 0}, {1, 1, 1});
    //init({-1, 0, 0, 1, 1, 1, 2, 2, 2}, {2, 3, 1, 4, 4, 3, 3, 3, 1});
    cout << query(1, 1) << ' ' << query(1, 2) << ' ' << query(3, 5);
    cout << ' ' << query(5, 10);
}*/

Compilation message (stderr)

tree.cpp: In function 'void dfs1(int, int)':
tree.cpp:94:42: warning: narrowing conversion of 'w[node]' from 'll' {aka 'long long int'} to 'int' [-Wnarrowing]
   94 |     upd(1, 0, timer+1, tin[node], {w[node], r-l});
      |                                    ~~~~~~^

• Subtask 0: 0 / 0
• Subtask 1: 0 / 10
• Subtask 2: 0 / 13
• Subtask 3: 0 / 18
• Subtask 4: 0 / 7
• Subtask 5: 0 / 11
• Subtask 6: 0 / 22
• Subtask 7: 0 / 19