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Submission #599503

# Submission time Handle Problem Language Result Execution time Memory
599503 2022-07-19T14:42:57 Z alexander707070 Event Hopping (BOI22_events) C++14
10 / 100
 1500 ms 136968 KB 
#include<bits/stdc++.h>
#define MAXN 400007
using namespace std;

struct event{
    long long s;
    long long e;
    int id;

    inline friend bool operator < (event fr,event sc){
        if(fr.e!=sc.e)return fr.e<sc.e;
        return fr.s<=sc.s;
    }
};

int n,cnt,q,S,E,ans;
int st[MAXN],et[MAXN];
int parent[MAXN];
event e[MAXN];
vector<int> w;
map<int,int> mp;

pair<int,int> mins[8*MAXN];

pair<int,int> best(pair<int,int> fr,pair<int,int> sc){
    if(fr.second<=sc.second)return fr;
    return sc;
}

void update(int v,int l,int r,int pos,int val,int id){
    if(l==r){
        if(val<mins[v].second or val==10000000){
            mins[v]={id,val};
        }
    }else{
        int tt=(l+r)/2;
        if(pos<=tt)update(2*v,l,tt,pos,val,id);
        else update(2*v+1,tt+1,r,pos,val,id);
        mins[v]=best(mins[2*v],mins[2*v+1]);
    }
}

pair<int,int> getmin(int v,int l,int r,int ll,int rr){
    if(ll>rr)return {0,100000000};
    if(l==ll and r==rr){
        return mins[v];
    }else{
        int tt=(l+r)/2;
        return best( getmin(2*v,l,tt,ll,min(tt,rr)) , getmin(2*v+1,tt+1,r,max(tt+1,ll),rr) );
    }
}

int dp[MAXN][20];

void calc(){
    for(int f=0;f<20;f++){
        for(int i=1;i<=n;i++){
            if(f==0)dp[i][f]=parent[i];
            else dp[i][f]=dp[dp[i][f-1]][f-1];
        }
    }
}

int bin(int id,int id2){

    if(id==id2)return 0;
    if(et[id]<st[id2])return -1;
    if(et[id2]>et[id])return -1;
    if(et[id2]>=st[id])return 1;

    int res=0;
    for(int i=19;i>=0;i--){
        if(dp[id][i]!=0 and st[dp[id][i]]>et[id2]){
            id=dp[id][i];
            res+=(1<<i);
        }
    }

    if(parent[id]==0)return -1;
    if(parent[id]==id2)return res+1;
    return res+2;
}

int main(){

    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    cin>>n>>q;
    for(int i=1;i<=n;i++){
        cin>>st[i]>>et[i];
        e[i]={st[i],et[i],i};
        w.push_back(e[i].s);
        w.push_back(e[i].e);
    }

    sort(w.begin(),w.end());
    for(int i=0;i<w.size();i++){
        if(i>0 and w[i]!=w[i-1])cnt++;
        mp[w[i]]=cnt;
    }

    for(int i=1;i<=n;i++){
        e[i].s=mp[e[i].s];
        e[i].e=mp[e[i].e];
    }

    for(int i=0;i<=cnt;i++){
        //update(1,0,cnt,i,10000000,0);
        mins[i]={0,10000000};
    }

     for(long long i=1;i<=100000000;i++){
        S=(E+3928)%30009; E=(S+2472)%20300;    
    }


    sort(e+1,e+n+1);

    for(int i=1;i<=n;i++){
        pair<int,int> sol={0,100000000};
        for(int f=e[i].s;f<=e[i].e;f++){
            sol=best(sol,mins[f]);
        }
        //parent[e[i].id]=getmin(1,0,cnt,e[i].s,e[i].e).first;
        parent[e[i].id]=sol.first;
        //update(1,0,cnt,e[i].e,e[i].s,e[i].id);
        mins[e[i].e]=best(mins[e[i].e],{e[i].id,e[i].s});
    }
    calc();

    for(int i=1;i<=q;i++){
        cin>>S>>E;
        ans=bin(E,S);
        if(ans==-1)cout<<"impossible\n";
        else cout<<ans<<"\n";
    }


    return 0;
}

Compilation message

events.cpp: In function 'int main()':
events.cpp:99:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   99 |     for(int i=0;i<w.size();i++){
      |                 ~^~~~~~~~~

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 724 ms 340 KB Output is correct
2 Correct 888 ms 18572 KB Output is correct
3 Correct 900 ms 18576 KB Output is correct
4 Correct 911 ms 18460 KB Output is correct
5 Correct 912 ms 19052 KB Output is correct
6 Correct 910 ms 19700 KB Output is correct
7 Correct 903 ms 19884 KB Output is correct
8 Correct 902 ms 24448 KB Output is correct
9 Correct 895 ms 24440 KB Output is correct
10 Correct 874 ms 18836 KB Output is correct
11 Correct 894 ms 21128 KB Output is correct
12 Correct 824 ms 18968 KB Output is correct

Subtask #2
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 737 ms 344 KB Output is correct
2 Correct 713 ms 340 KB Output is correct
3 Correct 740 ms 448 KB Output is correct
4 Correct 733 ms 444 KB Output is correct
5 Correct 728 ms 436 KB Output is correct
6 Correct 730 ms 460 KB Output is correct
7 Correct 731 ms 500 KB Output is correct
8 Correct 727 ms 488 KB Output is correct
9 Runtime error 894 ms 136968 KB Execution killed with signal 11
10 Halted 0 ms 0 KB -

Subtask #3
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 737 ms 344 KB Output is correct
2 Correct 713 ms 340 KB Output is correct
3 Correct 740 ms 448 KB Output is correct
4 Correct 733 ms 444 KB Output is correct
5 Correct 728 ms 436 KB Output is correct
6 Correct 730 ms 460 KB Output is correct
7 Correct 731 ms 500 KB Output is correct
8 Correct 727 ms 488 KB Output is correct
9 Runtime error 894 ms 136968 KB Execution killed with signal 11
10 Halted 0 ms 0 KB -

Subtask #4
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 737 ms 344 KB Output is correct
2 Correct 713 ms 340 KB Output is correct
3 Correct 740 ms 448 KB Output is correct
4 Correct 733 ms 444 KB Output is correct
5 Correct 728 ms 436 KB Output is correct
6 Correct 730 ms 460 KB Output is correct
7 Correct 731 ms 500 KB Output is correct
8 Correct 727 ms 488 KB Output is correct
9 Runtime error 894 ms 136968 KB Execution killed with signal 11
10 Halted 0 ms 0 KB -

Subtask #5
0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 920 ms 18576 KB Output is correct
2 Correct 913 ms 18500 KB Output is correct
3 Correct 958 ms 18456 KB Output is correct
4 Correct 923 ms 24500 KB Output is correct
5 Correct 907 ms 18836 KB Output is correct
6 Correct 946 ms 24276 KB Output is correct
7 Correct 952 ms 24180 KB Output is correct
8 Correct 956 ms 24444 KB Output is correct
9 Execution timed out 1589 ms 15600 KB Time limit exceeded
10 Halted 0 ms 0 KB -

Subtask #6
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 724 ms 340 KB Output is correct
2 Correct 888 ms 18572 KB Output is correct
3 Correct 900 ms 18576 KB Output is correct
4 Correct 911 ms 18460 KB Output is correct
5 Correct 912 ms 19052 KB Output is correct
6 Correct 910 ms 19700 KB Output is correct
7 Correct 903 ms 19884 KB Output is correct
8 Correct 902 ms 24448 KB Output is correct
9 Correct 895 ms 24440 KB Output is correct
10 Correct 874 ms 18836 KB Output is correct
11 Correct 894 ms 21128 KB Output is correct
12 Correct 824 ms 18968 KB Output is correct
13 Correct 737 ms 344 KB Output is correct
14 Correct 713 ms 340 KB Output is correct
15 Correct 740 ms 448 KB Output is correct
16 Correct 733 ms 444 KB Output is correct
17 Correct 728 ms 436 KB Output is correct
18 Correct 730 ms 460 KB Output is correct
19 Correct 731 ms 500 KB Output is correct
20 Correct 727 ms 488 KB Output is correct
21 Runtime error 894 ms 136968 KB Execution killed with signal 11
22 Halted 0 ms 0 KB -