oj.uz

답안 #1081780

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
1081780 2024-08-30T10:32:31 Z Tymond Event Hopping (BOI22_events) C++17
20 / 100
 752 ms 30320 KB 
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
#define fi first
#define se second
#define vi vector<int>
#define vll vector<long long>
#define pii pair<int, int>
#define pll pair<long long, long long>
#define pb push_back
#define mp make_pair
#define eb emplace_back
#define all(x) (x).begin(), (x).end()
#define sz(x) (int)(x).size()
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
mt19937_64 rng64(chrono::steady_clock::now().time_since_epoch().count());
inline int rand(int l,int r){return uniform_int_distribution<int>(l, r)(rng);}
inline ll rand(ll l,ll r){return uniform_int_distribution<ll>(l, r)(rng64);}
#ifdef DEBUG
auto&operator<<(auto&o,pair<auto,auto>p){return o<<"("<<p.first<<", "<<p.second<<")";}
auto operator<<(auto&o,auto x)->decltype(x.end(),o){o<<"{";int i=0;for(auto e:x)o<<","+!i++<<e;return o<<"}";}
#define debug(X...)cerr<<"["#X"]: ",[](auto...$){((cerr<<$<<"; "),...)<<endl;}(X)
#else
#define debug(...){}
#endif

struct custom_hash {
    static uint64_t splitmix64(uint64_t x) {
        x += 0x9e3779b97f4a7c15;
        x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
        x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
        return x ^ (x >> 31);
    }

    size_t operator()(uint64_t x) const {
        static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
        return splitmix64(x + FIXED_RANDOM);
    }
};

const int MAXN = 1e5 + 7;
const int BASE = (1 << 17);
const int MAXK = 20;
int pos[MAXN];
int tree[MAXK][2 * BASE + 7];
int range[MAXK][MAXN];
vector<pair<pii, int>> vec;
int n, q;

void upd(int k, int ind, int val){
    ind += BASE;
    tree[k][ind] = val;
    ind /= 2;
    while(ind > 0){
        tree[k][ind] = max(tree[k][2 * ind], tree[k][2 * ind + 1]);
        ind /= 2;
    }
}

int query(int v, int l, int p, int k, int a, int b){
    if(p < a || b < l){
        return 0;
    }

    if(a <= l && p <= b){
        return tree[k][v];
    }
    int mid = (l + p) / 2;
    return max(query(2 * v, l, mid, k, a, b), query(2 * v + 1, mid + 1, p, k, a, b));
}

void preprocessing(){
    //cout << "RANGES\n";
    for(int i = 0; i < n; i++){
        int l = i;
        int p = n - 1;
        int s;
        while(l < p){
            s = (l + p + 1) / 2;
            if(vec[i].fi.se < vec[s].fi.fi){
                p = s - 1;
            }else{
                l = s;
            }
        }
        //cout << i << ' ' << l << '\n';
        range[0][i] = l;
        upd(0, i, l);
    }

    for(int k = 1; k < MAXK; k++){
        for(int i = 0; i < n; i++){
            range[k][i] = query(1, 0, BASE - 1, k - 1, i, range[k - 1][i]);
            upd(k, i, range[k][i]);
        }
    }
}

int solve(int a, int b){
    if(range[19][a] < b){
        return -1;
    }

    int res = 0;
    int akt = a;
    for(int i = MAXK - 1; i >= 0; i--){
        int nr = query(1, 0, BASE - 1, i, a,akt);
        if(nr >= b){
            continue;
        }
        res += (1 << i);
        akt = nr;
    }

    return res + 1;
}

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    
    cin >> n >> q;
    for(int i = 1; i <= n; i++){
        int s,e;
        cin >> s >> e;
        vec.pb({{s, e}, i});
    }

    sort(all(vec));
    for(int i = 0; i < n; i++){
        pos[vec[i].se] = i;
    }

    preprocessing();

    /*for(auto ele : vec){
        cout << ele.fi.fi << ' ' << ele.fi.se << '\n';
    }

    for(int i = 0; i < n; i++){
        for(int j = 0; j < MAXK / 2; j++){
            cout << range[j][i] << ' ';
        }
        cout << '\n';
    }*/

    while(q--){
        int s, e;
        cin >> s >> e;
        s = pos[s];
        e = pos[e];
       // cout << "PYTANIE: " << s << ' ' << e << '\n';
        if(s == e){
            cout << 0 << '\n';
            continue;
        }

        if(s > e){
            if(vec[e].fi.se >= vec[s].fi.se){
                cout << 1 << '\n';
            }else{
                cout << "impossible\n";
            }
            continue;
        }

        int ans = solve(s, e);
        if(ans == -1){
            cout << "impossible\n";
        }else{
            cout << ans << '\n';
        }
    }

    return 0;
}

Subtask #1
0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 1112 KB Output is correct
2 Correct 594 ms 29808 KB Output is correct
3 Correct 749 ms 29964 KB Output is correct
4 Correct 730 ms 29908 KB Output is correct
5 Incorrect 699 ms 29884 KB Output isn't correct
6 Halted 0 ms 0 KB -

Subtask #2
0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 1116 KB Output is correct
2 Correct 1 ms 1236 KB Output is correct
3 Correct 4 ms 1548 KB Output is correct
4 Correct 4 ms 1372 KB Output is correct
5 Incorrect 4 ms 1372 KB Output isn't correct
6 Halted 0 ms 0 KB -

Subtask #3
0 / 15.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 1116 KB Output is correct
2 Correct 1 ms 1236 KB Output is correct
3 Correct 4 ms 1548 KB Output is correct
4 Correct 4 ms 1372 KB Output is correct
5 Incorrect 4 ms 1372 KB Output isn't correct
6 Halted 0 ms 0 KB -

Subtask #4
0 / 15.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 1116 KB Output is correct
2 Correct 1 ms 1236 KB Output is correct
3 Correct 4 ms 1548 KB Output is correct
4 Correct 4 ms 1372 KB Output is correct
5 Incorrect 4 ms 1372 KB Output isn't correct
6 Halted 0 ms 0 KB -

Subtask #5
20.0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Correct 589 ms 29892 KB Output is correct
2 Correct 752 ms 29800 KB Output is correct
3 Correct 708 ms 29888 KB Output is correct
4 Correct 333 ms 30320 KB Output is correct
5 Correct 490 ms 30148 KB Output is correct
6 Correct 569 ms 29892 KB Output is correct
7 Correct 577 ms 29884 KB Output is correct
8 Correct 499 ms 29988 KB Output is correct
9 Correct 370 ms 27952 KB Output is correct
10 Correct 671 ms 29636 KB Output is correct
11 Correct 600 ms 29632 KB Output is correct
12 Correct 663 ms 29640 KB Output is correct

Subtask #6
0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 1112 KB Output is correct
2 Correct 594 ms 29808 KB Output is correct
3 Correct 749 ms 29964 KB Output is correct
4 Correct 730 ms 29908 KB Output is correct
5 Incorrect 699 ms 29884 KB Output isn't correct
6 Halted 0 ms 0 KB -