Submission #1215945

#	Time	Username	Problem	Language	Result	Execution time	Memory
1215945		steveonalex	Comparing Plants (IOI20_plants)	C++20	100 / 100	722 ms	87328 KiB

plants

#include <bits/stdc++.h>
 
using namespace std;
 
typedef long long ll;
typedef unsigned long long ull;
 
#define MASK(i) (1LL << (i))
#define GETBIT(mask, i) (((mask) >> (i)) & 1)
#define ALL(v) (v).begin(), (v).end()
#define block_of_code if(true)
 
ll max(ll a, ll b){return (a > b) ? a : b;}
ll min(ll a, ll b){return (a < b) ? a : b;}
ll gcd(ll a, ll b){return __gcd(a, b);}
ll lcm(ll a, ll b){return a / gcd(a, b) * b;}
 
ll LASTBIT(ll mask){return (mask) & (-mask);}
int pop_cnt(ll mask){return __builtin_popcountll(mask);}
int ctz(ull mask){return __builtin_ctzll(mask);}
int logOf(ull mask){return 63 - __builtin_clzll(mask);}
 
mt19937_64 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
ll rngesus(ll l, ll r){return l + (ull) rng() % (r - l + 1);}
double rngesus_d(double l, double r){
    double cur = rngesus(0, MASK(60) - 1);
    cur /= MASK(60) - 1;
    return l + cur * (r - l);
}
 
template <class T1, class T2>
    bool maximize(T1 &a, T2 b){
        if (a < b) {a = b; return true;}
        return false;
    }
 
template <class T1, class T2>
    bool minimize(T1 &a, T2 b){
        if (a > b) {a = b; return true;}
        return false;
    }
 
template <class T>
    void printArr(T container, string separator = " ", string finish = "\n", ostream &out = cout){
        for(auto item: container) out << item << separator;
        out << finish;
    }
 
template <class T>
    void remove_dup(vector<T> &a){
        sort(ALL(a));
        a.resize(unique(ALL(a)) - a.begin());
    }

#include "plants.h"

ostream& operator << (ostream& os, pair<int, int> x){
    os << "(" << x.first << ", " << x.second << ")";
    return os;
}



struct SegmentTree{
    int n;
    vector<pair<int, int>> a;
    vector<int> lazy;

    SegmentTree(int _n, vector<int> b){
        n = _n;
        a.resize(n * 4 + 4);
        lazy.resize(n * 4 + 4);
        build_tree(0, n-1, 1, b);
    }

    void build_tree(int l, int r, int id, vector<int> &b){
        if (l == r) {
            a[id] = make_pair(b[l], l);
            return;
        }
        int mid = (l + r) >> 1;
        build_tree(l, mid, id * 2, b);
        build_tree(mid+1, r, id * 2 + 1, b);
        a[id] = min(a[id * 2], a[id * 2 + 1]);
    }

    void apply(int id, int la){
        a[id].first += la;
        lazy[id] += la;
    }

    void down(int id){
        apply(id * 2, lazy[id]); apply(id * 2 + 1, lazy[id]);
        lazy[id] = 0;
    }

    void update(int u, int v, int w, int l, int r, int id){
        if (u <= l && r <= v){
            apply(id, w);
            return;
        }
        if (lazy[id]) down(id);
        int mid = (l + r) >> 1;
        if (u <= mid) update(u, v, w, l, mid, id * 2);
        if (v > mid) update(u, v, w, mid+1, r, id * 2 + 1);
        a[id] = min(a[id * 2], a[id * 2 + 1]);
    }

    int normie(int x){
        x %= n;
        if (x < 0) x += n;
        return x;
    }

    void update(int u, int v, int w){
        u = normie(u);
        v = normie(v);
        if (u <= v)
            update(u, v, w, 0, n-1, 1);
        else{
            update(u, n-1, w, 0, n-1, 1);
            update(0, v, w, 0, n-1, 1);
        }
    }

    pair<int, int> get_min(){
        return a[1];
    }
};  

const int N = 2e5 + 69, LOG_N = 20;
const int INF = 1e9 + 69;
int n, k;
int order[N * 2];
int nxt1[LOG_N][N * 2], nxt2[LOG_N][N*2];


int normie(int x){
    x %= n;
    if (x < 0) x += n;
    return x;
}

void add_point(set<int> &all_pos, set<int> &valid_pos, int i){
    if (all_pos.empty()){
        all_pos.insert(i);
        valid_pos.insert(i);
        return;
    }
    int l = -1, r = -1;
    auto it = all_pos.upper_bound(i);
    if (it != all_pos.end())
        r = *it;
    if (it != all_pos.begin()){
        it--;
        l = *it;
    }

    if (l == -1) l = *all_pos.rbegin();
    if (r == -1) r = *all_pos.begin();

    valid_pos.erase(r);
    if (normie(r - i) >= k) valid_pos.insert(r);
    if (normie(i - l) >= k) valid_pos.insert(i);

    all_pos.insert(i);
}
void erase_point(set<int> &all_pos, set<int> &valid_pos, int i){
    all_pos.erase(i); 
    valid_pos.erase(i);

    if (all_pos.empty()) return;

    int l = -1, r = -1;
    auto it = all_pos.upper_bound(i);
    if (it != all_pos.end())
        r = *it;
    if (it != all_pos.begin()){
        it--;
        l = *it;
    }

    if (l == -1) l = *all_pos.rbegin();
    if (r == -1) r = *all_pos.begin();

    valid_pos.erase(r);
    if (normie(r - l) >= k || l == r) valid_pos.insert(r);
}

void init(int _k, vector<int> r){   
    n = r.size(), k = _k;

    SegmentTree st(n, r);
    set<int> all_pos;
    set<int> valid_pos;


    for(int it = 0; it < n; ++it){
        while(true){
            pair<int, int> cur = st.get_min();
            if (cur.first) break;
            int pos = cur.second;
            st.update(pos, pos, INF);
            add_point(all_pos, valid_pos, pos);
        }
        int pos = *valid_pos.begin();
        order[pos] = order[pos + n] = n - it;
        st.update(pos - k + 1, pos - 1, -1);
        erase_point(all_pos, valid_pos, pos);
    }

    set<pair<int, int>> S; S.insert(make_pair(0, 2 * n));
    nxt1[0][2*n] = 2*n;
    for(int i = 2 * n - 1; i >= 0; --i){
        if (i + k < 2 * n) S.erase(make_pair(order[i + k], i + k));

        auto it = S.upper_bound(make_pair(order[i], -1));
        if (it != S.begin()){
            it--;
            pair<int,int> cur = *it;
            nxt1[0][i] = cur.second;
        }

        S.insert(make_pair(order[i], i));
    }

    S.clear();
    S.insert(make_pair(0, -1));
    nxt2[0][0] = 0;
    for(int i = 0; i < 2 * n; ++i){
        if (i - k >= 0) S.erase(make_pair(order[i - k], i - k));

        auto it = S.upper_bound(make_pair(order[i], -1));
        if (it != S.begin()){
            it--;
            pair<int,int> cur = *it;
            nxt2[0][i + 1] = cur.second + 1;
        }

        S.insert(make_pair(order[i], i));
    }


    for(int j = 1; j < LOG_N; ++j) 
    for(int i = 0; i <= 2 * n; ++i){
        nxt1[j][i] = nxt1[j-1][nxt1[j-1][i]];
        nxt2[j][i] = nxt2[j-1][nxt2[j-1][i]];
    }
}

bool check_more_than(int x, int y){ 
    // check if (x) > (y)
    // walk from x to y
    if (y - x < k){
        return 1;
    }
    else{
        for(int j = LOG_N - 1; j >= 0; --j) {
            int _x = nxt1[j][x];
            if (y - _x >= k) x = _x;
        }
        x = nxt1[0][x];
        if (x == y || (x < y && order[x] > order[y])) return 1;
    }
    return 0;
}
bool check_less_than(int x, int y){ 
    // check if (x) < (y)
    // walk from y to x
    if (y - x < k){
        return 1;
    }
    else{
        for(int j = LOG_N - 1; j >= 0; --j) {
            int _y = nxt2[j][y+1]-1;
            if (_y - x >= k) y = _y;
        }
        y = nxt2[0][y+1]-1;
        if (x == y || (x < y && order[x] < order[y])) return 1;
    }
    return 0;
}


int compare_plants(int x, int y){
    if (order[x] > order[y]){ // either x is larger than y, or it is inconclusive
        if (check_more_than(x, y) || check_less_than(y, x + n)) return 1;
    }
    else{ // either x is larger than y, or it is inconclusive
        if (check_more_than(y, x + n) || check_less_than(x, y)) return -1;

    }
    return 0;
}

• Subtask 1: 5 / 5
• Subtask 2: 14 / 14
• Subtask 3: 13 / 13
• Subtask 4: 17 / 17
• Subtask 5: 11 / 11
• Subtask 6: 15 / 15
• Subtask 7: 25 / 25