oj.uz

Submission #595632

# Submission time Handle Problem Language Result Execution time Memory
595632 2022-07-13T22:25:12 Z definitelynotmee Event Hopping (BOI22_events) C++
30 / 100
 114 ms 11336 KB 
    #include<bits/stdc++.h>
    #define ff first
    #define ss second
    #define all(x) x.begin(), x.end()
    using namespace std;
    using ll = long long;
    using pii = pair<int,int>;
    using pll = pair<ll,ll>;
    template<typename T>
    using matrix = vector<vector<T>>;
    const int INF = 1<<30;
     
    int main() {
        cin.tie(0)->sync_with_stdio(0);
     
        int n, q;
        cin >> n >> q;
        vector<pii> v(n);
        for(pii& i : v){
            cin >> i.ff >> i.ss;
            i.ff = INF-i.ff;
            i.ss = INF-i.ss;
            swap(i.ff,i.ss);
        }
        // cout << "----------\n";
        // for(pii i : v)
        //     cout << i.ff << ' ' << i.ss << '\n';
        // cout << "----------\n";
        vector<int>o(n);
        iota(all(o),0);
        sort(all(o),[&](int a, int b){
            return v[a] > v[b];
        });
     
        vector<int> jmp(n);
        vector<int> st;
     
        for(int i : o){
            int ini = 0, fim = st.size();
            while(ini!=fim){
                int m = (ini+fim)>>1;
                if(v[st[m]].ff <= v[i].ss)
                    fim = m;
                else ini = m+1;
            }
            if(ini == st.size()){
                jmp[i] = i;
            } else jmp[i] = st[ini];
            
            while(!st.empty() && v[st.back()].ss <= v[i].ss)
                st.pop_back();
            if(st.empty() || v[st.back()].ff > v[i].ff)
                st.push_back(i);
            // cout << i << ":\n";
            // for(int i : st)
            //     cout << i << ' ';
            // cout << '\n';
        }
     
        matrix<int> lift(20,vector<int>(n));
        for(int i = 0; i < n; i++){
            lift[0][i] = jmp[i]; 
            // cout << jmp[i] << ' ';
        }
        // cout << '\n';
        for(int i = 1; i < 20; i++){
            for(int j = 0; j < n; j++){
                lift[i][j] = lift[i-1][lift[i-1][j]];
            }
        }
        
        while(q--){
            int a, b;
            cin >> a >> b;
            a--, b--;
            swap(a,b);
            if(v[a] > v[b]){
                cout << "impossible\n";
                continue;
            }
            if(a == b){
                cout << 0 << '\n';
                continue;
            }
            if(v[a].ss >= v[b].ff){
                cout << 1 << '\n';
                continue;
            }
            int ct = 2;
            for(int i = 19; i >= 0; i--){
                if(v[lift[i][a]].ss < v[b].ff)
                    ct+=1<<i, a = lift[i][a];
            }
            a = lift[0][a];
            if(v[a].ss >= v[b].ff){
                cout << ct << '\n';
            } else {
                cout << "impossible\n";
            }
        }
     
    }

Compilation message

events.cpp: In function 'int main()':
events.cpp:46:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   46 |             if(ini == st.size()){
      |                ~~~~^~~~~~~~~~~~

Subtask #1
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 67 ms 10828 KB Output is correct
3 Correct 82 ms 10772 KB Output is correct
4 Correct 114 ms 10828 KB Output is correct
5 Correct 83 ms 10840 KB Output is correct
6 Correct 80 ms 10832 KB Output is correct
7 Correct 83 ms 10828 KB Output is correct
8 Correct 96 ms 11336 KB Output is correct
9 Correct 99 ms 11336 KB Output is correct
10 Correct 84 ms 11208 KB Output is correct
11 Incorrect 84 ms 11080 KB Output isn't correct
12 Halted 0 ms 0 KB -

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 1 ms 340 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 1 ms 340 KB Output is correct
8 Correct 1 ms 340 KB Output is correct
9 Correct 1 ms 340 KB Output is correct

Subtask #3
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 1 ms 340 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 1 ms 340 KB Output is correct
8 Correct 1 ms 340 KB Output is correct
9 Correct 1 ms 340 KB Output is correct
10 Correct 0 ms 212 KB Output is correct
11 Correct 0 ms 212 KB Output is correct
12 Correct 1 ms 340 KB Output is correct
13 Correct 1 ms 340 KB Output is correct
14 Correct 1 ms 340 KB Output is correct
15 Correct 1 ms 340 KB Output is correct
16 Correct 1 ms 340 KB Output is correct
17 Correct 1 ms 340 KB Output is correct
18 Correct 1 ms 340 KB Output is correct
19 Correct 40 ms 1296 KB Output is correct
20 Correct 29 ms 1324 KB Output is correct
21 Correct 30 ms 1548 KB Output is correct
22 Incorrect 24 ms 1512 KB Output isn't correct
23 Halted 0 ms 0 KB -

Subtask #4
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 1 ms 340 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 1 ms 340 KB Output is correct
8 Correct 1 ms 340 KB Output is correct
9 Correct 1 ms 340 KB Output is correct
10 Correct 0 ms 212 KB Output is correct
11 Correct 0 ms 212 KB Output is correct
12 Correct 1 ms 340 KB Output is correct
13 Correct 1 ms 340 KB Output is correct
14 Correct 1 ms 340 KB Output is correct
15 Correct 1 ms 444 KB Output is correct
16 Correct 1 ms 340 KB Output is correct
17 Correct 1 ms 340 KB Output is correct
18 Correct 1 ms 340 KB Output is correct
19 Correct 37 ms 10592 KB Output is correct
20 Correct 34 ms 10572 KB Output is correct
21 Correct 36 ms 10084 KB Output is correct
22 Incorrect 37 ms 10456 KB Output isn't correct
23 Halted 0 ms 0 KB -

Subtask #5
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 62 ms 10824 KB Output is correct
2 Correct 78 ms 10860 KB Output is correct
3 Correct 102 ms 10836 KB Output is correct
4 Correct 95 ms 11328 KB Output is correct
5 Correct 85 ms 11200 KB Output is correct
6 Correct 83 ms 11032 KB Output is correct
7 Correct 77 ms 10960 KB Output is correct
8 Correct 72 ms 11104 KB Output is correct
9 Correct 35 ms 10572 KB Output is correct
10 Correct 73 ms 10640 KB Output is correct
11 Correct 69 ms 10604 KB Output is correct
12 Correct 74 ms 10648 KB Output is correct

Subtask #6
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 67 ms 10828 KB Output is correct
3 Correct 82 ms 10772 KB Output is correct
4 Correct 114 ms 10828 KB Output is correct
5 Correct 83 ms 10840 KB Output is correct
6 Correct 80 ms 10832 KB Output is correct
7 Correct 83 ms 10828 KB Output is correct
8 Correct 96 ms 11336 KB Output is correct
9 Correct 99 ms 11336 KB Output is correct
10 Correct 84 ms 11208 KB Output is correct
11 Incorrect 84 ms 11080 KB Output isn't correct
12 Halted 0 ms 0 KB -