oj.uz

Submission #779556

# Submission time Handle Problem Language Result Execution time Memory
779556 2023-07-11T14:17:29 Z CpDark Event Hopping (BOI22_events) C++14
30 / 100
 114 ms 19752 KB 
#include <bits/stdc++.h>

using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<int, int> pii;
typedef vector<pii> vp;
typedef vector<vp> vvp;
typedef vector<bool> vb;
typedef vector<vb> vvb;
typedef vector<ll> vll;
typedef vector<vll> vvll;

const ll inf = 1e18 + 7;

vvp table;
vp events;
vector<pair<int,pii>> endTimes;
int mylog;

int query(int start, int end) {
    if (events[start].second > events[end].second)return -1;
    if (start == end)return 0;
    int wall = events[start].second;
    int jumps = 0;
    
    for (int i = mylog;i >= 0;i--) {
        if (table[i][end].second > wall) {
            jumps += 1 << i;
            end = table[i][end].first;
        }
    }
    jumps++;
    end = table[0][end].first;
    if (events[end].second <= wall && events[start].first >= events[end].first)return jumps;
    return -1;
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    
    int n, q;
    cin >> n >> q;
    mylog = ceil(log2(n + 1));
    events.resize(n);
    endTimes.resize(n);
    table.resize(mylog + 1, vp(n));
    
    for (int i = 0;i < n;i++) {
        cin >> events[i].first >> events[i].second;
        endTimes[i] = { events[i].second, {events[i].first, i} };
    }
 
    sort(endTimes.begin(), endTimes.end());
 
    for (int i = 0;i < endTimes.size();i++) {
        int index = endTimes[i].second.second;
        int far = lower_bound(endTimes.begin(), endTimes.end(), (pair<int, pii>){ events[index].first, make_pair(-1,-1)}) - endTimes.begin();
        table[0][index] = { endTimes[far].second.second, endTimes[far].first};
    }
 
    for (int i = 1;i <= mylog;i++) {
        for (int v = 0;v < n;v++) {
            int p = table[i - 1][v].first;
            table[i][v] = table[i - 1][p];
        }
    }
 
    int s, e;
    for (int i = 0;i < q;i++) {
        cin >> s >> e;
        s--; e--;
        int ans = query(s, e);
        if (ans == -1) {
            cout << "impossible\n";
        }
        else {
            cout << ans << '\n';
        }
    }
 
    return 0;
}

Compilation message

events.cpp: In function 'int main()':
events.cpp:58:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, std::pair<int, int> > >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   58 |     for (int i = 0;i < endTimes.size();i++) {
      |                    ~~^~~~~~~~~~~~~~~~~

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 58 ms 17236 KB Output is correct
3 Correct 75 ms 17248 KB Output is correct
4 Correct 92 ms 17372 KB Output is correct
5 Correct 82 ms 17396 KB Output is correct
6 Correct 78 ms 17392 KB Output is correct
7 Correct 82 ms 17452 KB Output is correct
8 Correct 89 ms 17828 KB Output is correct
9 Correct 88 ms 17828 KB Output is correct
10 Correct 76 ms 17724 KB Output is correct
11 Correct 83 ms 17756 KB Output is correct
12 Correct 58 ms 19752 KB Output is correct

Subtask #2
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 1 ms 332 KB Output is correct
4 Correct 1 ms 332 KB Output is correct
5 Correct 1 ms 340 KB Output is correct
6 Incorrect 1 ms 340 KB Output isn't correct
7 Halted 0 ms 0 KB -

Subtask #3
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 1 ms 332 KB Output is correct
4 Correct 1 ms 332 KB Output is correct
5 Correct 1 ms 340 KB Output is correct
6 Incorrect 1 ms 340 KB Output isn't correct
7 Halted 0 ms 0 KB -

Subtask #4
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 1 ms 332 KB Output is correct
4 Correct 1 ms 332 KB Output is correct
5 Correct 1 ms 340 KB Output is correct
6 Incorrect 1 ms 340 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 58 ms 17220 KB Output is correct
2 Correct 76 ms 17196 KB Output is correct
3 Correct 114 ms 17368 KB Output is correct
4 Correct 90 ms 17888 KB Output is correct
5 Correct 85 ms 17696 KB Output is correct
6 Correct 80 ms 17444 KB Output is correct
7 Correct 85 ms 17492 KB Output is correct
8 Correct 67 ms 17572 KB Output is correct
9 Correct 33 ms 17236 KB Output is correct
10 Correct 70 ms 17236 KB Output is correct
11 Correct 66 ms 17156 KB Output is correct
12 Correct 72 ms 17236 KB Output is correct

Subtask #6
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 58 ms 17236 KB Output is correct
3 Correct 75 ms 17248 KB Output is correct
4 Correct 92 ms 17372 KB Output is correct
5 Correct 82 ms 17396 KB Output is correct
6 Correct 78 ms 17392 KB Output is correct
7 Correct 82 ms 17452 KB Output is correct
8 Correct 89 ms 17828 KB Output is correct
9 Correct 88 ms 17828 KB Output is correct
10 Correct 76 ms 17724 KB Output is correct
11 Correct 83 ms 17756 KB Output is correct
12 Correct 58 ms 19752 KB Output is correct
13 Correct 1 ms 212 KB Output is correct
14 Correct 1 ms 212 KB Output is correct
15 Correct 1 ms 332 KB Output is correct
16 Correct 1 ms 332 KB Output is correct
17 Correct 1 ms 340 KB Output is correct
18 Incorrect 1 ms 340 KB Output isn't correct
19 Halted 0 ms 0 KB -