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Submission #1002233

# Submission time Handle Problem Language Result Execution time Memory
1002233 2024-06-19T11:15:10 Z Andrey Event Hopping (BOI22_events) C++14
10 / 100
 67 ms 25804 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 7768 KB Output is correct
2 Correct 55 ms 21340 KB Output is correct
3 Correct 55 ms 21328 KB Output is correct
4 Correct 59 ms 21212 KB Output is correct
5 Correct 55 ms 21324 KB Output is correct
6 Correct 57 ms 24400 KB Output is correct
7 Correct 58 ms 24380 KB Output is correct
8 Correct 47 ms 25804 KB Output is correct
9 Correct 44 ms 24916 KB Output is correct
10 Correct 67 ms 24632 KB Output is correct
11 Correct 64 ms 24908 KB Output is correct
12 Correct 48 ms 24156 KB Output is correct

Subtask #2
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 7772 KB Output is correct
2 Correct 2 ms 7768 KB Output is correct
3 Correct 2 ms 8024 KB Output is correct
4 Correct 3 ms 8028 KB Output is correct
5 Correct 4 ms 8028 KB Output is correct
6 Incorrect 2 ms 7940 KB Output isn't correct
7 Halted 0 ms 0 KB -

Subtask #3
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 7772 KB Output is correct
2 Correct 2 ms 7768 KB Output is correct
3 Correct 2 ms 8024 KB Output is correct
4 Correct 3 ms 8028 KB Output is correct
5 Correct 4 ms 8028 KB Output is correct
6 Incorrect 2 ms 7940 KB Output isn't correct
7 Halted 0 ms 0 KB -

Subtask #4
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 7772 KB Output is correct
2 Correct 2 ms 7768 KB Output is correct
3 Correct 2 ms 8024 KB Output is correct
4 Correct 3 ms 8028 KB Output is correct
5 Correct 4 ms 8028 KB Output is correct
6 Incorrect 2 ms 7940 KB Output isn't correct
7 Halted 0 ms 0 KB -

Subtask #5
0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 55 ms 21220 KB Output is correct
2 Correct 60 ms 21332 KB Output is correct
3 Correct 59 ms 21332 KB Output is correct
4 Correct 53 ms 21844 KB Output is correct
5 Correct 65 ms 21584 KB Output is correct
6 Incorrect 65 ms 21328 KB Output isn't correct
7 Halted 0 ms 0 KB -

Subtask #6
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 7768 KB Output is correct
2 Correct 55 ms 21340 KB Output is correct
3 Correct 55 ms 21328 KB Output is correct
4 Correct 59 ms 21212 KB Output is correct
5 Correct 55 ms 21324 KB Output is correct
6 Correct 57 ms 24400 KB Output is correct
7 Correct 58 ms 24380 KB Output is correct
8 Correct 47 ms 25804 KB Output is correct
9 Correct 44 ms 24916 KB Output is correct
10 Correct 67 ms 24632 KB Output is correct
11 Correct 64 ms 24908 KB Output is correct
12 Correct 48 ms 24156 KB Output is correct
13 Correct 2 ms 7772 KB Output is correct
14 Correct 2 ms 7768 KB Output is correct
15 Correct 2 ms 8024 KB Output is correct
16 Correct 3 ms 8028 KB Output is correct
17 Correct 4 ms 8028 KB Output is correct
18 Incorrect 2 ms 7940 KB Output isn't correct
19 Halted 0 ms 0 KB -