Submission #1080361

#	Time	Username	Problem	Language	Result	Execution time	Memory
1080361		GrindMachine	Comparing Plants (IOI20_plants)	C++17	15 / 100	620 ms	31784 KiB

plants

#include <bits/stdc++.h>
using namespace std;

typedef long long int ll;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;

#define pb push_back
#define endl '\n'
#define conts continue
#define sz(a) (int)a.size()
#define ff first
#define ss second
#define all(a) a.begin(),a.end()
#define rall(a) a.rbegin(),a.rend()

#define rep(i,n) for(int i = 0; i < n; ++i)
#define rep1(i,n) for(int i = 1; i <= n; ++i)
#define rev(i,s,e) for(int i = s; i >= e; ++i)
#define trav(i,a) for(auto &i : a)

template<typename T>
void amin(T &x, T y){
    x = min(x,y);
}

template<typename T>
void amax(T &x, T y){
    x = max(x,y);
}

template<typename A,typename B>
string to_string(pair<A,B> p);

string to_string(const string &s){
    return "'"+s+"'";
}

string to_string(const char* s){
    return to_string((string)s);
}

string to_string(bool b){
    return b?"true":"false";
}

template<typename A>
string to_string(A v){
    string res = "{";
    trav(x,v){
        res += to_string(x)+",";
    }
    if(res.back() == ',') res.pop_back();
    res += "}";
    return res;
}

template<typename A,typename B>
string to_string(pair<A,B> p){
    return "("+to_string(p.ff)+","+to_string(p.ss)+")";
}

#define debug(x) cout << "[" << #x << "]: "; cout << to_string(x) << endl

const int MOD = 1e9 + 7;
const int N = 1<<18;
const int inf1 = 1e9 + 5;
const ll inf2 = (ll)1e18 + 5;

#include "plants.h"

pii d_neutral = {inf1,-1};
vector<pii> tr(4*N,d_neutral);
vector<int> lz(4*N);

void propagate(int x, int lx, int rx){
    int v = lz[x];
    tr[x].ff += v;

    if(rx-lx > 1){
        lz[x<<1] += v;
        lz[x<<1|1] += v;
    }

    lz[x] = 0;
}

void rupd(int x, int lx, int rx, int l, int r, int v){
    propagate(x,lx,rx);

    if(lx >= r or rx <= l) return;
    if(lx >= l and rx <= r){
        lz[x] = v;
        propagate(x,lx,rx);
        return;
    }

    int mid = (lx+rx)>>1;
    rupd(x<<1,lx,mid,l,r,v);
    rupd(x<<1|1,mid,rx,l,r,v);

    tr[x] = min(tr[x<<1],tr[x<<1|1]);
}

void rupd(int l, int r, int v){
    rupd(1,0,N,l,r+1,v);
}

pii query(){
    propagate(1,0,N);
    return tr[1];
}

pii query(int x, int lx, int rx, int l, int r){
    propagate(x,lx,rx);
    if(lx >= r or rx <= l) return d_neutral;
    if(lx >= l and rx <= r) return tr[x];
    int mid = (lx+rx)>>1;
    return min(query(x<<1,lx,mid,l,r),query(x<<1|1,mid,rx,l,r));
}

pii query(int l, int r){
    return query(1,0,N,l,r+1);
}

void build(int x, int lx, int rx, vector<int> &a){
    if(rx-lx == 1){
        if(lx < sz(a)){
            tr[x] = {a[lx],lx};
        }
        return;
    }

    int mid = (lx+rx) >> 1;
    build(x<<1,lx,mid,a);
    build(x<<1|1,mid,rx,a);
    tr[x] = min(tr[x<<1],tr[x<<1|1]);
}

void build(vector<int> &a){
    build(1,0,N,a);
}

void init_st(){
    fill(all(tr),d_neutral);
    fill(all(lz),0);
}

vector<int> id;
vector<int> adj[N];
vector<bool> reach_from_0(N), reach_to_0(N);

void init(int k, std::vector<int> a) {
    k--;
    int n = sz(a);
    id = vector<int>(n);
    build(a);

    int iter = 0;
    int rem_cnt = 0;

    auto rem = [&](int i){
        rem_cnt++;
        id[i] = iter;
        if(i-k >= 0){
            rupd(i-k,i-1,-1);
        }
        else{
            rupd(0,i-1,-1);
            rupd(i-k+n,n-1,-1);
        }
    };

    set<int> zeros;
    set<pii> dis;

    while(rem_cnt < n){
        iter++;

        while(true){
            auto [mn,i] = query();
            if(mn == 0){
                rupd(i,i,inf1);

                zeros.insert(i);
                auto it = zeros.find(i);
                int prevv = -1, nxt = -1;
                if(it != zeros.begin()){
                    prevv = *prev(it);
                }
                if(next(it) != zeros.end()){
                    nxt = *next(it);
                }

                if(prevv != -1 and nxt != -1) dis.erase({nxt-prevv,nxt});
                if(prevv != -1) dis.insert({i-prevv,i});
                if(nxt != -1) dis.insert({nxt-i,nxt});
            }
            else{
                break;
            }
        }

        if(sz(zeros) == 1){
            trav(i,zeros){
                rem(i);
            }

            zeros.clear();
            dis.clear();
            conts;
        }

        vector<int> del;

        {
            int i = *zeros.begin(), j = *zeros.rbegin();
            int d = (i-j+n)%n;
            if(d > k){
                del.pb(i);
            }            
        }

        for(auto it = dis.rbegin(); it != dis.rend(); ++it){
            auto [d,i] = *it;
            if(d > k){
                del.pb(i);
            }
            else{
                break;
            }
        }

        trav(i,del){
            rem(i);

            auto it = zeros.find(i);
            int prevv = -1, nxt = -1;
            if(it != zeros.begin()){
                prevv = *prev(it);
            }
            if(next(it) != zeros.end()){
                nxt = *next(it);
            }

            zeros.erase(it);

            if(prevv != -1) dis.erase({i-prevv,i});
            if(nxt != -1) dis.erase({nxt-i,nxt});
            if(prevv != -1 and nxt != -1) dis.insert({nxt-prevv,nxt});
        }
    }

    init_st();
    rep(i,n) id[i] = -id[i];
    build(id);

    {
        queue<int> q;
        q.push(0);
        rupd(0,0,inf1);

        while(!q.empty()){
            int i = q.front();
            q.pop();
            reach_from_0[i] = 1;

            vector<pii> ranges;
            if(i+k < n){
                ranges.pb({i+1,i+k});
            }
            else{
                ranges.pb({i+1,n-1});
                ranges.pb({0,(i+k)%n});
            }

            if(i-k >= 0){
                ranges.pb({i-k,i-1});
            }
            else{
                ranges.pb({0,i-k});
                ranges.pb({i-k+n,n-1});
            }

            for(auto [l,r] : ranges){
                if(l > r) conts;
                while(true){
                    auto [mn,j] = query(l,r);
                    if(mn > n) break;
                    if(id[i] < id[j]) break;
                    q.push(j);
                    rupd(j,j,inf1);   
                }
            }
        }
    }

    init_st();
    rep(i,n) id[i] = -id[i];
    build(id);

    {
        queue<int> q;
        q.push(0);
        rupd(0,0,inf1);

        while(!q.empty()){
            int i = q.front();
            q.pop();
            reach_to_0[i] = 1;

            vector<pii> ranges;
            if(i+k < n){
                ranges.pb({i+1,i+k});
            }
            else{
                ranges.pb({i+1,n-1});
                ranges.pb({0,(i+k)%n});
            }

            if(i-k >= 0){
                ranges.pb({i-k,i-1});
            }
            else{
                ranges.pb({0,i-k});
                ranges.pb({i-k+n,n-1});
            }

            for(auto [l,r] : ranges){
                if(l > r) conts;
                while(true){
                    auto [mn,j] = query(l,r);
                    if(mn > n) break;
                    if(id[i] < id[j]) break;
                    q.push(j);
                    rupd(j,j,inf1);   
                }
            }
        }
    }
}

int compare_plants(int x, int y) {
    if(reach_from_0[y]) return 1;
    if(reach_to_0[y]) return -1;
    return 0;
}

• Subtask 1: 0 / 5
• Subtask 2: 0 / 14
• Subtask 3: 0 / 13
• Subtask 4: 0 / 17
• Subtask 5: 0 / 11
• Subtask 6: 15 / 15
• Subtask 7: 0 / 25