Submission #878941

#	Time	Username	Problem	Language	Result	Execution time	Memory
878941		Tymond	Railway Trip 2 (JOI22_ho_t4)	C++17	100 / 100	791 ms	383144 KiB

Main

#include <bits/stdc++.h>
using namespace std;
#define fi first
#define sec second
 
const int BASE = 1024 * 1024;
const int MAXK = 21;
 
pair<int, int> tree[2 * BASE + 7][MAXK];
pair<int, int> wDol[2 * BASE + 7];
pair<int, int> skacz[BASE + 7][MAXK];
int n, k;
 
void init(){
    for(int i = 0; i < BASE; i++){
        for(int j = 0; j < MAXK; j++){
            tree[i + BASE][j] = {i, i};
        }
    }
    
    for(int i = BASE - 1; i >= 1; i--){
        for(int j = 0; j < MAXK; j++){
            tree[i][j].fi = min(tree[2 * i][j].fi, tree[2 * i + 1][j].fi);
            tree[i][j].sec = max(tree[2 * i][j].sec, tree[2 * i + 1][j].sec);
        }
    }
    
    for(int i = 0; i < 2 * BASE; i++){
        wDol[i] = {1e9, -1e9};
    }
}
 
void pchnij(int v, int dep){
    tree[2 * v][dep].fi = min(tree[2 * v][dep].fi, wDol[v].fi);
    tree[2 * v][dep].sec = max(tree[2 * v][dep].sec, wDol[v].sec);
    wDol[2 * v].fi = min(wDol[2 * v].fi, wDol[v].fi);
    wDol[2 * v].sec = max(wDol[2 * v].sec, wDol[v].sec);
    
    tree[2 * v + 1][dep].fi = min(tree[2 * v + 1][dep].fi, wDol[v].fi);
    tree[2 * v + 1][dep].sec = max(tree[2 * v + 1][dep].sec, wDol[v].sec);
    wDol[2 * v + 1].fi = min(wDol[2 * v + 1].fi, wDol[v].fi);
    wDol[2 * v + 1].sec = max(wDol[2 * v + 1].sec, wDol[v].sec);
    
    wDol[v] = {1e9, -1e9};
}
 
int depth, a, b, val;
void update(int v, int l, int p){
    if(p < a || b < l){
        return;
    }
    
    if(a <= l && p <= b){
        tree[v][depth].fi = min(tree[v][depth].fi, val);
        tree[v][depth].sec = max(tree[v][depth].sec, val);
        
        wDol[v].fi = min(wDol[v].fi, val);
        wDol[v].sec = max(wDol[v].sec, val);
        
        return;
    }
    
    pchnij(v, depth);
    
    int mid = (l + p) / 2;
    update(2 * v, l, mid);
    update(2 * v + 1, mid + 1, p);
    
    tree[v][depth].fi = min(tree[2 * v][depth].fi, tree[2 * v + 1][depth].fi);
    tree[v][depth].sec = max(tree[2 * v][depth].sec, tree[2 * v + 1][depth].sec);
}

pair<int, int> query(int v, int l, int p){
    if(p < a || b < l){
        return {1e9, -1e9};
    }
    
    if(a <= l && p <= b){
        return tree[v][depth];
    }
    
    pchnij(v, depth);
    
    int mid = (l + p) / 2;
    pair<int, int> lewo = query(2 * v, l, mid);
    pair<int, int> prawo = query(2 * v + 1, mid + 1, p);
    
    return {min(lewo.fi, prawo.fi), max(lewo.sec, prawo.sec)};
}

pair<int, int> q2(){
    a += BASE;
    a--;
    b += BASE;
    b++;
    
    pair<int, int> res = {1e9, -1e9};
    while(a / 2 != b / 2){
        if(a % 2 == 0){
            res.fi = min(res.fi, tree[a + 1][depth].fi);
            res.sec = max(res.sec, tree[a + 1][depth].sec);
        }
        
        if(b & 1){
            res.fi = min(res.fi, tree[b- 1][depth].fi);
            res.sec = max(res.sec, tree[b - 1][depth].sec);
        }
        
        a = a / 2;
        b = b / 2;
    }
   // cerr << res.first << ' ' << res.second << '\n';
    return res;
}
 
void upd(int v){
    v += BASE;
    while(v >= 1){
        tree[v][depth].fi = min(tree[v][depth].fi, a);
        tree[v][depth].sec = max(tree[v][depth].sec, b);
        v /= 2;
    }
}
 
void getAns(int start, int cel){
    if(start == cel){
        cout << 0 << '\n';
        return;
    }
    
    int ans = 0;
    pair<int, int> akt = {start, start};
    for(int i = MAXK - 1; i >= 0; i--){
        depth = i;
        a = akt.fi;
        b = akt.sec;
        pair<int, int> zapyt = q2();
        if(cel < zapyt.fi || cel > zapyt.sec){
            if(i == MAXK - 1){
                cout << -1 << '\n';
                return;
            }
            ans = ans + (1 << i);
            akt = zapyt;
        }
    }
    
    cout << ans + 1 << '\n';
}
 
int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    
    cin >> n >> k;
    
    init();
    int m;
 
    cin >> m;
    int x, l;
    for(int i = 1; i <= m; i++){
        cin >> x >> l;
        //x--;
       // l--;
        if(x < l){
            depth = 0;
            a = x;
            b = min(x + k - 1, l);
            val = l;
            update(1, 0, BASE - 1);
        }else{
            depth = 0;
            a = max(x - k + 1, l);
            b = x;
            val = l;
            update(1, 0, BASE - 1);
        }
    }

 
    for(int i = 1; i <= n; i++){
        a = i;
        b = i;
        depth = 0;
        skacz[i][0] = query(1, 0, BASE - 1);
    }

 
    for(int dep = 1; dep < MAXK; dep++){
        for(int i = 1; i <= n; i++){
            depth = dep - 1;
            a = skacz[i][dep - 1].fi;
            b = skacz[i][dep - 1].sec;
            skacz[i][dep] = q2();
            a = skacz[i][dep].fi;
            b = skacz[i][dep].sec;
            depth = dep;
            upd(i);
        }
    }

    int q;
    cin >> q;
    
    int s, t;
    for(int i = 1; i <= q; i++){
        cin >> s >> t;
       // s--;
        //t--;
        getAns(s, t);
    }
 
    return 0;
}

• Subtask 1: 8 / 8
• Subtask 2: 8 / 8
• Subtask 3: 11 / 11
• Subtask 4: 25 / 25
• Subtask 5: 35 / 35
• Subtask 6: 13 / 13