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Submission #1002260

# Submission time Handle Problem Language Result Execution time Memory
1002260 2024-06-19T11:36:07 Z Andrey Event Hopping (BOI22_events) C++14
30 / 100
 74 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 || bruh[a] >= wow[b]) {
                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 5720 KB Output is correct
2 Correct 59 ms 24400 KB Output is correct
3 Correct 74 ms 24396 KB Output is correct
4 Correct 64 ms 24404 KB Output is correct
5 Correct 60 ms 24400 KB Output is correct
6 Correct 59 ms 24524 KB Output is correct
7 Correct 63 ms 24556 KB Output is correct
8 Correct 53 ms 25804 KB Output is correct
9 Correct 47 ms 24912 KB Output is correct
10 Correct 71 ms 24656 KB Output is correct
11 Correct 65 ms 24912 KB Output is correct
12 Correct 42 ms 24144 KB Output is correct

Subtask #2
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 5972 KB Output is correct
2 Correct 2 ms 5720 KB Output is correct
3 Correct 2 ms 5980 KB Output is correct
4 Correct 2 ms 6004 KB Output is correct
5 Correct 2 ms 5980 KB Output is correct
6 Incorrect 2 ms 5980 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 5972 KB Output is correct
2 Correct 2 ms 5720 KB Output is correct
3 Correct 2 ms 5980 KB Output is correct
4 Correct 2 ms 6004 KB Output is correct
5 Correct 2 ms 5980 KB Output is correct
6 Incorrect 2 ms 5980 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 5972 KB Output is correct
2 Correct 2 ms 5720 KB Output is correct
3 Correct 2 ms 5980 KB Output is correct
4 Correct 2 ms 6004 KB Output is correct
5 Correct 2 ms 5980 KB Output is correct
6 Incorrect 2 ms 5980 KB Output isn't correct
7 Halted 0 ms 0 KB -

Subtask #5
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 66 ms 24404 KB Output is correct
2 Correct 64 ms 24400 KB Output is correct
3 Correct 64 ms 24400 KB Output is correct
4 Correct 46 ms 24912 KB Output is correct
5 Correct 72 ms 24864 KB Output is correct
6 Correct 71 ms 24516 KB Output is correct
7 Correct 70 ms 24400 KB Output is correct
8 Correct 71 ms 24660 KB Output is correct
9 Correct 40 ms 23500 KB Output is correct
10 Correct 65 ms 24148 KB Output is correct
11 Correct 65 ms 24280 KB Output is correct
12 Correct 65 ms 24144 KB Output is correct

Subtask #6
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 5720 KB Output is correct
2 Correct 59 ms 24400 KB Output is correct
3 Correct 74 ms 24396 KB Output is correct
4 Correct 64 ms 24404 KB Output is correct
5 Correct 60 ms 24400 KB Output is correct
6 Correct 59 ms 24524 KB Output is correct
7 Correct 63 ms 24556 KB Output is correct
8 Correct 53 ms 25804 KB Output is correct
9 Correct 47 ms 24912 KB Output is correct
10 Correct 71 ms 24656 KB Output is correct
11 Correct 65 ms 24912 KB Output is correct
12 Correct 42 ms 24144 KB Output is correct
13 Correct 2 ms 5972 KB Output is correct
14 Correct 2 ms 5720 KB Output is correct
15 Correct 2 ms 5980 KB Output is correct
16 Correct 2 ms 6004 KB Output is correct
17 Correct 2 ms 5980 KB Output is correct
18 Incorrect 2 ms 5980 KB Output isn't correct
19 Halted 0 ms 0 KB -