oj.uz

Submission #736176

# Submission time Handle Problem Language Result Execution time Memory
736176 2023-05-05T09:42:55 Z ksu2009en Event Hopping (BOI22_events) C++14
10 / 100
 1500 ms 118880 KB 
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx,avx2")

#include <iostream>
#include <vector>
#include <string>
#include <math.h>
#include <cmath>
#include <iomanip>
#include <cstdio>
#include <algorithm>
#include <numeric>
#include <map>
#include <set>
#include <queue>
#include <stack>
#include <deque>
#include <bitset>
#include <cstring>
#include <unordered_map>

using namespace std;
typedef int ll;

struct one{
    ll first, second, ind;
};

bool cmp(one p1, one p2){
    if(p1.second == p2.second)
        return p1.first < p2.first;
    return p1.second < p2.second;
}

void compress(vector<one> &a){
    vector<ll>b;
    for(auto i: a){
        b.push_back(i.first);
        b.push_back(i.second);
    }
    
    sort(b.begin(), b.end());
    b.resize(unique(b.begin(), b.end()) - b.begin());
    
    ll step = 1;
    map<ll, ll> mp;
    for(auto i: b)
        mp[i] = step++;
    
    for(auto &i: a){
        i.first = mp[i.first];
        i.second = mp[i.second];
    }
}

ll dp[2 * 5007][2 * 5007];
vector<ll>start_here[2 * 5007];

vector<one>a;

void count_dp(one fin){
    for(int i = 0; i < a.size(); i++)
        dp[i][fin.ind] = 1e9;
    
    dp[fin.ind][fin.ind] = 0;
    
    bool ok = false;
    
    multiset<ll>st;
    
    for(int ind = a.size() - 1; ind >= 0; ind--){
        auto i = a[ind];
        
        if(i.ind == fin.ind){
            //cout << i.ind << ' ' << ind << endl;
            ok = true;
            st.insert(0);
        }
        else if(ok){
            if(st.empty()){
               // cout << "st.empty() " << i.ind << endl;
                dp[i.ind][fin.ind] = 1e9;
                st.insert(1e9);
            }
            else{
              //  cout << i.ind << endl;
              //  for(auto j: st)
              //      cout << j << ' ';
              //  cout << endl;
                dp[i.ind][fin.ind] = *st.begin();
                if(*st.begin() != (ll)(1e9))
                    dp[i.ind][fin.ind]++;
                                
                st.insert(dp[i.ind][fin.ind]);
            }
        }
        else{
           // cout << "not yet " << i.ind << endl;
            st.insert(1e9);
        }
        
        if(ind - 1 >= 0){
            for(int del = i.second; del > a[ind - 1].second; del--)
                for(auto j: start_here[del]){
                    st.erase(st.find(dp[j][fin.ind]));
                }
        }
    }
}

vector<ll>count_dp2(ll start){
    vector<ll>dp2(a.size(), 1e9);
    
    dp2[start] = 0;
    
    for(auto i: a){
        for(auto j: a){
            if(i.first <= j.second && j.second <= i.second){
                dp2[i.ind] = min(dp2[i.ind], dp2[j.ind] + 1);
            }
        }
    }
    
    return dp2;
}
#define endl '\n'

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    
    ll n, q;
    cin >> n >> q;
    
    a.resize(n);
    for(int i = 0; i < n; i++){
        cin >> a[i].first >> a[i].second;
        a[i].ind = i;
    }
    
    compress(a);
    sort(a.begin(), a.end(), cmp);

    
    for(auto i: a)
        start_here[i.first].push_back(i.ind);
    
    for(auto i: a){
        count_dp(i);
    }
   
    while(q--){
        ll l, r;
        cin >> l >> r;
        //l = 1 + rand() % n, r = 1 + rand() % n;
        
        l--, r--;
        
        //auto dp2 = count_dp2(l);
        
        if(dp[l][r] == (ll)(1e9))
            cout << "impossible" << endl;
        else{
            cout << dp[l][r] << endl;
        }
    }
     
    return 0;
}
/*
 8 1
 1 2
 3 4
 1 5
 6 7
 5 10
 10 20
 15 20
 999999999 1000000000
 1 7
 
 
 */
/*
 1 2
 1 1000000000
 
 */
/*
 5 9
 2 0
 
 */
/*
 10 100
 1 3
 4 6
 2 8
 8 23
 1 4
 2 4
 6 73
 2 34
 1 9
 8 90
 
 2 3
 
 
 */

Compilation message

events.cpp: In function 'void count_dp(one)':
events.cpp:62:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<one>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   62 |     for(int i = 0; i < a.size(); i++)
      |                    ~~^~~~~~~~~~

Subtask #1
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 596 KB Output is correct
2 Runtime error 265 ms 99660 KB Execution killed with signal 11
3 Halted 0 ms 0 KB -

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 468 KB Output is correct
2 Correct 1 ms 468 KB Output is correct
3 Correct 61 ms 8616 KB Output is correct
4 Correct 51 ms 8628 KB Output is correct
5 Correct 72 ms 8616 KB Output is correct
6 Correct 133 ms 8656 KB Output is correct
7 Correct 161 ms 8664 KB Output is correct
8 Correct 91 ms 8668 KB Output is correct
9 Correct 82 ms 8592 KB Output is correct

Subtask #3
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 468 KB Output is correct
2 Correct 1 ms 468 KB Output is correct
3 Correct 61 ms 8616 KB Output is correct
4 Correct 51 ms 8628 KB Output is correct
5 Correct 72 ms 8616 KB Output is correct
6 Correct 133 ms 8656 KB Output is correct
7 Correct 161 ms 8664 KB Output is correct
8 Correct 91 ms 8668 KB Output is correct
9 Correct 82 ms 8592 KB Output is correct
10 Correct 1 ms 468 KB Output is correct
11 Correct 0 ms 468 KB Output is correct
12 Correct 49 ms 8616 KB Output is correct
13 Correct 45 ms 8528 KB Output is correct
14 Correct 57 ms 8616 KB Output is correct
15 Correct 156 ms 8600 KB Output is correct
16 Correct 176 ms 8664 KB Output is correct
17 Correct 99 ms 8664 KB Output is correct
18 Correct 90 ms 8584 KB Output is correct
19 Execution timed out 1578 ms 118880 KB Time limit exceeded
20 Halted 0 ms 0 KB -

Subtask #4
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 468 KB Output is correct
2 Correct 1 ms 468 KB Output is correct
3 Correct 61 ms 8616 KB Output is correct
4 Correct 51 ms 8628 KB Output is correct
5 Correct 72 ms 8616 KB Output is correct
6 Correct 133 ms 8656 KB Output is correct
7 Correct 161 ms 8664 KB Output is correct
8 Correct 91 ms 8668 KB Output is correct
9 Correct 82 ms 8592 KB Output is correct
10 Correct 1 ms 468 KB Output is correct
11 Correct 1 ms 596 KB Output is correct
12 Correct 60 ms 8620 KB Output is correct
13 Correct 49 ms 8628 KB Output is correct
14 Correct 61 ms 8536 KB Output is correct
15 Correct 133 ms 8600 KB Output is correct
16 Correct 165 ms 8664 KB Output is correct
17 Correct 100 ms 8664 KB Output is correct
18 Correct 106 ms 8584 KB Output is correct
19 Runtime error 276 ms 99564 KB Execution killed with signal 11
20 Halted 0 ms 0 KB -

Subtask #5
0 / 20.0

# Verdict Execution time Memory Grader output
1 Runtime error 260 ms 99580 KB Execution killed with signal 11
2 Halted 0 ms 0 KB -

Subtask #6
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 596 KB Output is correct
2 Runtime error 265 ms 99660 KB Execution killed with signal 11
3 Halted 0 ms 0 KB -