Submission #682994

#	Time	Username	Problem	Language	Result	Execution time	Memory
682994		Ahmed57	Queue (CEOI06_queue)	C++14	66 / 100	261 ms	16052 KiB

queue

#include <bits/stdc++.h>

using namespace std;
map<int,int> nex,pre;
int next(int x){
    if(nex.count(x))return nex[x];
    return x+1;
}int prev(int x){
    if(pre.count(x))return pre[x];
    return x-1;
}
int inf = 1e9;
int main(){
    int val = 1;
    int n;
    cin>>n;
    while(n--){
        int a,b;
        cin>>a>>b;
        nex[prev(a)] = next(a);
        pre[next(a)] = prev(a);
        int la = prev(b);
        nex[la] = a;
        pre[a] = la;
        nex[a] = b;
        pre[b] = a;
        if(b==val){
            val= a;
        }
    }
    nex[inf] = inf+1;
    vector<pair<int,int>> v;
    if(nex[1]==0){
        nex[1] = 2;
    }
    auto it = nex.begin();
    while(1){
        if(val==inf)break;
        if(!nex.count(val)){
            auto pp = nex.lower_bound(val+1);
            long long ne = (*pp).first;
            v.push_back({val,ne-val});
            val = ne;
            continue;
        }else{
            long long ne= nex[val];
            v.push_back({val,1});
            val= ne;
            continue;
        }
    }
    int q;cin>>q;
    set<pair<int,int>> L,R;
    for(int i = 0;i<q;i++){
        char c;cin>>c;
        long long x;cin>>x;
        if(c=='L'){
            L.insert({x,i});
        }else{
            R.insert({x,i});
        }
    }
    long long ans[q] = {0};
    int st = 0, cur = 1;
    for(auto i:L){
        while(st<v.size()&&cur+v[st].second<=i.first)cur+=v[st].second,st++;
        ans[i.second] = v[st].first+(i.first-cur);
    }
    int sum = 1;
    for(int i = 0;i<v.size();i++){
        if(v[i].second==1){
            pair<int,int> p = {v[i].first,0};
            auto it = R.lower_bound(p);
            if(it!=R.end()&&(*it).first==v[i].first){
                ans[(*it).second] = sum;
            }
        }else{
            int l = v[i].first , r = v[i].second+v[i].first-1;
            pair<int,int> p = {l,0};
            auto it = R.lower_bound(p);
            while(it!=R.end()&&(*it).first<=r){
                ans[(*it).second] = sum+((*it).first-l);
                it++;
            }
        }
        sum+=v[i].second;
    }
    for(int i = 0;i<q;i++){
        cout<<ans[i]<<"\n";
    }
}

Compilation message (stderr)

queue.cpp: In function 'int main()':
queue.cpp:66:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   66 |         while(st<v.size()&&cur+v[st].second<=i.first)cur+=v[st].second,st++;
      |               ~~^~~~~~~~~
queue.cpp:70:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   70 |     for(int i = 0;i<v.size();i++){
      |                   ~^~~~~~~~~
queue.cpp:36:10: warning: variable 'it' set but not used [-Wunused-but-set-variable]
   36 |     auto it = nex.begin();
      |          ^~

• Subtask 1: 66 / 100