oj.uz

Submission #736180

# Submission time Handle Problem Language Result Execution time Memory
736180 2023-05-05T09:46:28 Z ksu2009en Event Hopping (BOI22_events) C++14
10 / 100
 1500 ms 120136 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;
            }
            else{
              //  cout << i.ind << endl;
              //  for(auto j: st)
              //      cout << j << ' ';
              //  cout << endl;
                dp[i.ind][fin.ind] = *st.begin();
                dp[i.ind][fin.ind]++;
                                
                st.insert(dp[i.ind][fin.ind]);
            }
        }
        else{
           // cout << "not yet " << i.ind << endl;
        }
        
        if(ind - 1 >= 0){
            for(int del = i.second; del > a[ind - 1].second; del--)
                for(auto j: start_here[del]){
                    if(st.find(dp[j][fin.ind]) != st.end())
                        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 468 KB Output is correct
2 Runtime error 242 ms 99724 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 0 ms 596 KB Output is correct
3 Correct 32 ms 8532 KB Output is correct
4 Correct 25 ms 8640 KB Output is correct
5 Correct 30 ms 8532 KB Output is correct
6 Correct 50 ms 8600 KB Output is correct
7 Correct 86 ms 8664 KB Output is correct
8 Correct 57 ms 8672 KB Output is correct
9 Correct 56 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 0 ms 596 KB Output is correct
3 Correct 32 ms 8532 KB Output is correct
4 Correct 25 ms 8640 KB Output is correct
5 Correct 30 ms 8532 KB Output is correct
6 Correct 50 ms 8600 KB Output is correct
7 Correct 86 ms 8664 KB Output is correct
8 Correct 57 ms 8672 KB Output is correct
9 Correct 56 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 36 ms 8628 KB Output is correct
13 Correct 22 ms 8632 KB Output is correct
14 Correct 32 ms 8576 KB Output is correct
15 Correct 55 ms 8616 KB Output is correct
16 Correct 87 ms 8660 KB Output is correct
17 Correct 47 ms 8660 KB Output is correct
18 Correct 48 ms 8604 KB Output is correct
19 Execution timed out 1524 ms 120136 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 0 ms 596 KB Output is correct
3 Correct 32 ms 8532 KB Output is correct
4 Correct 25 ms 8640 KB Output is correct
5 Correct 30 ms 8532 KB Output is correct
6 Correct 50 ms 8600 KB Output is correct
7 Correct 86 ms 8664 KB Output is correct
8 Correct 57 ms 8672 KB Output is correct
9 Correct 56 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 31 ms 8628 KB Output is correct
13 Correct 28 ms 8532 KB Output is correct
14 Correct 33 ms 8616 KB Output is correct
15 Correct 49 ms 8532 KB Output is correct
16 Correct 90 ms 8660 KB Output is correct
17 Correct 50 ms 8664 KB Output is correct
18 Correct 56 ms 8588 KB Output is correct
19 Runtime error 281 ms 99664 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 243 ms 99680 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 468 KB Output is correct
2 Runtime error 242 ms 99724 KB Execution killed with signal 11
3 Halted 0 ms 0 KB -