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Submission #1002247

# Submission time Handle Problem Language Result Execution time Memory
1002247 2024-06-19T11:23:44 Z Andrey Event Hopping (BOI22_events) C++14
30 / 100
 84 ms 22736 KB 
#include<bits/stdc++.h>
using namespace std;

vector<int> bruh(200001);
vector<int> wow(200001);
vector<pair<int,int>> seg(500001);

void build(int l, int r, int x) {
    if(l == r) {
        seg[x] = {wow[l],l};
        return;
    }
    int m = (l+r)/2;
    build(l,m,x*2);
    build(m+1,r,x*2+1);
    seg[x] = min(seg[x*2],seg[x*2+1]);
}

pair<int,int> calc(int l, int r, int x, int ql, int qr) {
    if(l == ql && r == qr) {
        return seg[x];
    }
    int m = (l+r)/2;
    if(qr <= m) {
        return calc(l,m,x*2,ql,qr);
    }
    else if(ql > m) {
        return calc(m+1,r,x*2+1,ql,qr);
    }
    else {
        return min(calc(l,m,x*2,ql,m),calc(m+1,r,x*2+1,m+1,qr));
    }
}

int apple[100001][17];
int banana[100001][17];

int main()
{
    ios_base::sync_with_stdio(NULL);
    cin.tie(NULL);
    cout.tie(NULL);
    int n,q,a,b;
    cin >> n >> q;
    vector<pair<pair<int,int>,int>> haha(n+1);
    for(int i = 1; i <= n; i++) {
        cin >> a >> b;
        haha[i] = {{b,a},i};
    }
    sort(haha.begin(),haha.end());
    vector<int> pos(n+1);
    for(int i = 1; i <= n; i++) {
        pos[haha[i].second] = i;
        bruh[i] = haha[i].first.first;
        wow[i] = haha[i].first.second;
    }
    priority_queue<pair<int,int>> idk;
    for(int i = n; i >= 1; i--) {
        while(!idk.empty() && idk.top().second > bruh[i]) {
            idk.pop();
        }
        if(idk.empty()) {
            apple[i][0] = -1;
        }
        else {
            apple[i][0] = idk.top().first;
        }
        idk.push({i,wow[i]});
    }
    build(1,n,1);
    for(int i = 1; i <= n; i++) {
        int l,r;
        if(i == 1 || bruh[i-1] < wow[i]) {
            banana[i][0] = -1;
        }
        else{ 
            l = 1,r = i-1;
            while(l < r) {
                int m = (l+r)/2;
                if(bruh[l] < wow[i]) {
                    l = m+1;
                }
                else {
                    r = m;
                }
            }
            banana[i][0] = calc(1,n,1,l,i-1).second;
        }
    }
    for(int i = 1; i < 17; i++) {
        for(int j = 1; j <= n; j++) {
            if(apple[j][i-1] == -1) {
                apple[j][i] = -1;
            }
            else {
                apple[j][i] = apple[apple[j][i-1]][i-1];
            }
            if(banana[j][i-1] == -1) {
                banana[j][i] = -1;
            }
            else {
                banana[j][i] = banana[banana[j][i-1]][i-1];
            }
        }
    }
    for(int i = 0; i < q; i++) {
        cin >> a >> b;
        a = pos[a];
        b = pos[b];
        if(a > b) {
            if(bruh[a] == bruh[b]) {
                cout << 1 << "\n";
            }
            else {
                cout << "impossible\n";
            }
            continue;
        }
        int ans = 0;
        for(int j = 16; j >= 0; j--) {
            if(apple[a][j] == -1 || apple[a][j] > b) {
                continue;
            }
            ans+=(1 << j);
            a = apple[a][j];
        }
        if(a == b) {
            cout << ans << "\n";
            continue;
        }
        /*for(int j = 16; j >= 0; j--) {
            if(banana[b][j] == -1 || banana[b][j] < a) {
                continue;
            }
            ans+=(1 << j);
            b = banana[b][j];
        }*/
        if(b == a) {
            cout << ans << "\n";
        }
        else if(wow[b] <= bruh[a]) {
            cout << ans+1 << "\n";
        }
        else {
            cout << "impossible\n";
        }
    }
    return 0;
}

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 7772 KB Output is correct
2 Correct 63 ms 21320 KB Output is correct
3 Correct 56 ms 21388 KB Output is correct
4 Correct 73 ms 21212 KB Output is correct
5 Correct 56 ms 21464 KB Output is correct
6 Correct 55 ms 21436 KB Output is correct
7 Correct 54 ms 21328 KB Output is correct
8 Correct 44 ms 22736 KB Output is correct
9 Correct 47 ms 21844 KB Output is correct
10 Correct 69 ms 21580 KB Output is correct
11 Correct 74 ms 21576 KB Output is correct
12 Correct 61 ms 21836 KB Output is correct

Subtask #2
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 7768 KB Output is correct
2 Correct 2 ms 7768 KB Output is correct
3 Correct 3 ms 8024 KB Output is correct
4 Correct 2 ms 8028 KB Output is correct
5 Incorrect 3 ms 8028 KB Output isn't correct
6 Halted 0 ms 0 KB -

Subtask #3
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 7768 KB Output is correct
2 Correct 2 ms 7768 KB Output is correct
3 Correct 3 ms 8024 KB Output is correct
4 Correct 2 ms 8028 KB Output is correct
5 Incorrect 3 ms 8028 KB Output isn't correct
6 Halted 0 ms 0 KB -

Subtask #4
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 7768 KB Output is correct
2 Correct 2 ms 7768 KB Output is correct
3 Correct 3 ms 8024 KB Output is correct
4 Correct 2 ms 8028 KB Output is correct
5 Incorrect 3 ms 8028 KB Output isn't correct
6 Halted 0 ms 0 KB -

Subtask #5
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 55 ms 21336 KB Output is correct
2 Correct 60 ms 21324 KB Output is correct
3 Correct 60 ms 21336 KB Output is correct
4 Correct 47 ms 21836 KB Output is correct
5 Correct 62 ms 21728 KB Output is correct
6 Correct 66 ms 21332 KB Output is correct
7 Correct 65 ms 21332 KB Output is correct
8 Correct 65 ms 21584 KB Output is correct
9 Correct 42 ms 21708 KB Output is correct
10 Correct 84 ms 21208 KB Output is correct
11 Correct 60 ms 21140 KB Output is correct
12 Correct 61 ms 21072 KB Output is correct

Subtask #6
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 7772 KB Output is correct
2 Correct 63 ms 21320 KB Output is correct
3 Correct 56 ms 21388 KB Output is correct
4 Correct 73 ms 21212 KB Output is correct
5 Correct 56 ms 21464 KB Output is correct
6 Correct 55 ms 21436 KB Output is correct
7 Correct 54 ms 21328 KB Output is correct
8 Correct 44 ms 22736 KB Output is correct
9 Correct 47 ms 21844 KB Output is correct
10 Correct 69 ms 21580 KB Output is correct
11 Correct 74 ms 21576 KB Output is correct
12 Correct 61 ms 21836 KB Output is correct
13 Correct 2 ms 7768 KB Output is correct
14 Correct 2 ms 7768 KB Output is correct
15 Correct 3 ms 8024 KB Output is correct
16 Correct 2 ms 8028 KB Output is correct
17 Incorrect 3 ms 8028 KB Output isn't correct
18 Halted 0 ms 0 KB -