Submission #421657

#	Time	Username	Problem	Language	Result	Execution time	Memory
421657		Aldas25	Fountain (eJOI20_fountain)	C++14	100 / 100	1150 ms	35976 KiB

fountain

#include <bits/stdc++.h>

using namespace std;

#define FAST_IO ios_base::sync_with_stdio(0); cin.tie(nullptr)
#define FOR(i, a, b) for (int i = (a); i <= (b); i++)
#define REP(n) FOR(O, 1, (n))
#define f first
#define s second
#define pb push_back
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<pii> vii;

const int MAXN = 500100, MAXK = 20;
const ll INF = 1e16;
const ll MOD = 1e9+7;

int n, q;
ll d[MAXN], c[MAXN];
vii srt;
set<int> cur;

int par[MAXN][MAXK];
ll sum[MAXN][MAXK];

void build () {
    FOR(i, 1, MAXK-1) {
        FOR(v, 1, n) {
            par[v][i] = par[par[v][i-1]][i-1];
            sum[v][i] = sum[v][i-1] + sum[par[v][i-1]][i-1];
        }
    }
}

ll getSum (int v, int i) {
    ll ret = 0ll;
    FOR(j, 0, MAXK-1) {
        if (i & (1<<j)) {
            ret += sum[v][j];
            v = par[v][j];
        }
    }
    return ret;
}

int lift (int v, int i) {
    FOR(j, 0, MAXK-1)
        if (i & (1<<j))
            v = par[v][j];
    return v;
}

int query (int r, ll v) {
    //cout << " query r = " << r << " v = " << v << endl;

    int le = 0, ri = n;
    while (le < ri) {
        int mid = (le+ri)/2;

        //cout << " mid = " << mid << " getSum = " << getSum(r, mid+1) << endl;

        if (getSum(r, mid+1) < v) le = mid+1;
        else ri = mid;
    }
    int ret = lift(r, le);
    if (ret == n+1) return 0;
    else return ret;
}

int main()
{
    FAST_IO;

    cin >> n >> q;
    FOR(i, 1, n) {
        cin >> d[i] >> c[i];
        srt.pb({-d[i], i});
        sum[i][0] = c[i];
    }

    sum[n+1][0] = 1e9+5;

    sort(srt.begin(), srt.end());

    cur.insert(n+1);
    for (auto p : srt) {
        int id = p.s;
        auto it = cur.upper_bound(id);
        par[id][0] = (*it);
        cur.insert(id);
    }

    //FOR(i, 1, n) cout << " i=" << i << " to = " << par[i][0] << endl;

    build ();

    REP(q) {
        int r; ll v;
        cin >> r >> v;
        cout << query(r,v) << "\n";
    }

    return 0;
}

• Subtask 1: 30 / 30
• Subtask 2: 30 / 30
• Subtask 3: 40 / 40