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Submission #1002236

# Submission time Handle Problem Language Result Execution time Memory
1002236 2024-06-19T11:17:06 Z Andrey Event Hopping (BOI22_events) C++14
30 / 100
 73 ms 24780 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 65 ms 21332 KB Output is correct
3 Correct 47 ms 21332 KB Output is correct
4 Correct 62 ms 21328 KB Output is correct
5 Correct 70 ms 21328 KB Output is correct
6 Correct 55 ms 21488 KB Output is correct
7 Correct 56 ms 21328 KB Output is correct
8 Correct 38 ms 22744 KB Output is correct
9 Correct 42 ms 21724 KB Output is correct
10 Correct 73 ms 21584 KB Output is correct
11 Correct 56 ms 21584 KB Output is correct
12 Correct 36 ms 21844 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 7820 KB Output is correct
3 Correct 2 ms 8028 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 7820 KB Output is correct
3 Correct 2 ms 8028 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 7820 KB Output is correct
3 Correct 2 ms 8028 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 47 ms 21324 KB Output is correct
2 Correct 48 ms 21364 KB Output is correct
3 Correct 51 ms 21332 KB Output is correct
4 Correct 37 ms 21840 KB Output is correct
5 Correct 66 ms 21588 KB Output is correct
6 Correct 54 ms 21328 KB Output is correct
7 Correct 63 ms 24392 KB Output is correct
8 Correct 61 ms 24780 KB Output is correct
9 Correct 37 ms 23500 KB Output is correct
10 Correct 64 ms 24400 KB Output is correct
11 Correct 60 ms 24276 KB Output is correct
12 Correct 63 ms 24144 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 65 ms 21332 KB Output is correct
3 Correct 47 ms 21332 KB Output is correct
4 Correct 62 ms 21328 KB Output is correct
5 Correct 70 ms 21328 KB Output is correct
6 Correct 55 ms 21488 KB Output is correct
7 Correct 56 ms 21328 KB Output is correct
8 Correct 38 ms 22744 KB Output is correct
9 Correct 42 ms 21724 KB Output is correct
10 Correct 73 ms 21584 KB Output is correct
11 Correct 56 ms 21584 KB Output is correct
12 Correct 36 ms 21844 KB Output is correct
13 Correct 2 ms 7768 KB Output is correct
14 Correct 2 ms 7820 KB Output is correct
15 Correct 2 ms 8028 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 -