Submission #1087028

#	Time	Username	Problem	Language	Result	Execution time	Memory
1087028		alexander707070	Strange Device (APIO19_strange_device)	C++14	100 / 100	353 ms	69088 KiB

strange_device

#include<bits/stdc++.h>
#define MAXN 1000007
using namespace std;

const long long inf=1e18+7;

int n;
pair<long long,long long> p[MAXN];
long long A,B;

vector< pair<long long,long long> > v;
long long ans,last;

int main(){

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

    cin>>n>>A>>B;
    
    long long cycle=A/__gcd(A,B+1);
    
    if(cycle>inf/B)cycle=inf;
    else cycle*=B;

    for(int i=1;i<=n;i++){
        cin>>p[i].first>>p[i].second;

        if(p[i].second-p[i].first+1>=cycle){
            cout<<cycle<<"\n";
            return 0;
        }

        p[i].first%=cycle; p[i].second%=cycle;
        
        if(p[i].first<=p[i].second){
            v.push_back({p[i].first,p[i].second});
        }else{
            v.push_back({0,p[i].second});
            v.push_back({p[i].first,cycle-1});
        }
    }

    sort(v.begin(),v.end());

    last=-1;
    for(int i=0;i<v.size();i++){
        ans+=max(0LL , v[i].second-max(v[i].first-1,last));

        last=max(last,v[i].second);
    }

    cout<<ans<<"\n";

    return 0;

}

Compilation message (stderr)

strange_device.cpp: In function 'int main()':
strange_device.cpp:48:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   48 |     for(int i=0;i<v.size();i++){
      |                 ~^~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 5 / 5
• Subtask 3: 5 / 5
• Subtask 4: 5 / 5
• Subtask 5: 5 / 5
• Subtask 6: 20 / 20
• Subtask 7: 20 / 20
• Subtask 8: 30 / 30