Submission #602688

#	Time	Username	Problem	Language	Result	Execution time	Memory
602688		almothana05	Event Hopping (BOI22_events)	C++14	100 / 100	1223 ms	46988 KiB

events

#include<bits/stdc++.h>
#define mod 1000000007
using namespace std;
vector<vector<int> >num;
vector<pair<int , int > >cmp;
vector<int>pow2;
int ind[200000] , platz[200000];
int lift[300000][20], seg[20][800000];
unordered_map<int , int>trans;
int sucher(int id , int l , int r , int gewl , int gewr , int ver){
    if(gewl > r || l > gewr){
        return mod;
    }
    if(gewl <= l && r <= gewr){
        return seg[ver][id];
    }
    int m = (l + r)/2;
    return min(sucher(id * 2 , l , m , gewl , gewr , ver) , sucher(id * 2 + 1 , m + 1 , r , gewl ,gewr , ver));
}
int main(){
    int menge , numm , nummer , que , len;
    cin >> menge >> que;
    for(int i = 1 ; i < 1000000 ; i*= 2){
        pow2.push_back(i);
    }
    for(len = 1 ; len < 100000 ; len *= 2);
    for(int i = 0 ; i < menge ; i++){
        platz[i + 1]  = -1;
        cin >> numm >> nummer;
        num.push_back({nummer , numm , i + 1});
        cmp.push_back({numm , 0});
        cmp.push_back({nummer , 1});
    }
    int pl = 0;// does matter sort begin?
    sort(cmp.begin() , cmp.end());
    sort(num.begin() , num.end());
    for(int i = cmp.size() - 1 ; i >= 0; i--){
        if(trans[cmp[i].first] == 0 && cmp[i].second == 1){
            // cout << cmp[i].first << ' ';
            pl++;
        }//////////////////////////////////////////////////////////////
        trans[cmp[i].first] = pl;
    }
    pl++;
    // cout << "\n";
    for(int i = 0 ; i < num.size() ; i++){
        // cout << num[i][0] << ' ' << num[i][1] << "\n";
        num[i][0] = pl - trans[num[i][0]];
        num[i][1] = pl - trans[num[i][1]];
        ind[num[i][2]] = i;
        if(platz[num[i][0]] == -1){
            platz[num[i][0]] = i;
        }
        lift[i][0] = num[i][1];
        // cout << num[i][0]<< ' ' << num[i][1]<< "\n\n";
    }
    for(int i = 1 ; i < 20 ; i++){
        // cout << i << ' ';
        for(int j = 0 ; j < 100000; j++){
            seg[i - 1][j + len] = lift[j][i - 1];
        }
        for(int j = len - 1 ; j > 0 ; j--){
            seg[i - 1][j] = min(seg[i - 1][j * 2] , seg[i - 1][j * 2 + 1]);
        }
        for(int j = 0 ; j < num.size(); j++){
            lift[j][i] = sucher(1 , 1 , len , platz[lift[j][i - 1]] + 1 , j + 1 , i - 1);
        }
        // cout << i  << " \n";
    }
    // for(int i = 0 ; i < menge ; i++){
    //     for(int j = 0 ; j < 20 ; j++){
    //         cout << lift[i][j] << ' ';
    //     }
    //     cout << "\n";
    // }
    int erg;
    while(que--){
        erg = 0;
        cin >> numm >> nummer;
        if(numm == nummer){
            cout << 0 << "\n";
            continue;
        }
        numm = ind[numm];
        nummer = ind[nummer];
        // cout << numm <<' ' << nummer  << "\n";
        if(num[numm][0] > num[nummer][0]){
            cout << "impossible\n";
            continue;
        }
        int be = nummer , en = nummer;
        for(int i = 19 ; i >= 0 ; i--){
            int comp = sucher(1 , 1, len , be + 1 , en + 1 , i ) ;
                // cout << comp << " ";
            if( comp > num[numm][0]){
                // cout << i << ' ' ;
                erg += pow2[i];
                be = platz[comp];
            }
        }
        // cout << "\n";
        // cout <<  nummer << " \n";
        be = platz[sucher(1 , 1, len , be + 1 , en + 1 , 0 )];
        // cout << numm << ' ' << be << ' ' << en << "\n";
        if(numm >= be){
            cout << erg + 1 << "\n";
        }
        else{
            cout << "impossible\n";
        }
    }
}

Compilation message (stderr)

events.cpp: In function 'int main()':
events.cpp:46:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   46 |     for(int i = 0 ; i < num.size() ; i++){
      |                     ~~^~~~~~~~~~~~
events.cpp:65:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   65 |         for(int j = 0 ; j < num.size(); j++){
      |                         ~~^~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 15 / 15
• Subtask 4: 15 / 15
• Subtask 5: 20 / 20
• Subtask 6: 30 / 30