Submission #402081

#	Time	Username	Problem	Language	Result	Execution time	Memory
402081		Blobo2_Blobo2	Strange Device (APIO19_strange_device)	C++14	100 / 100	591 ms	28248 KiB

strange_device

/*
Editor: Abdelrahman Hossam
Nickname: Blobo2_Blobo2
IOI next year isA :)
*/

//#pragma GCC optimize ("O3")
//#pragma GCC optimize ("unroll-loops")
#include<bits/stdc++.h>
#define int long long
#define endl "\n"
#define all(v)  v.begin(),v.end()
#define gen(arr,n,nxt)  generate(arr,arr+n,nxt)
#define base ios_base::sync_with_stdio(false);cin.tie(0);

using namespace std;
const int mo=1e9+7;
int nxt(){int x;cin>>x;return x;}

signed main(){
    base
    int n=nxt(),a=nxt(),b=nxt();
    a/=__gcd(a,b+1);
    int x=1000000000000000001;
    vector<pair<int,int> >v;
    if(a<=LLONG_MAX/b)
        x=a*b;
    bool flag=0;
    for(int i=0;i<n;i++){
        int first=nxt(),sec=nxt();
        if(sec-first+1>=x)flag=1;
        else if(sec%x<first%x){
            first%=x;
            sec%=x;
            v.push_back({first,x-1});
            v.push_back({0,sec});
        }
        else v.push_back({first%x,sec%x});
    }
    if(flag){
        cout<<x<<endl;
        return 0;
    }
    sort(all(v));
    int cnt=0,l=v[0].first,r=v[0].second;
    for(int i=0;i<v.size();i++){
        if(v[i].first<=r)r=max(r,v[i].second);
        else{
            cnt+=r-l+1;
            r=v[i].second;
            l=v[i].first;
        }
    }
    cnt+=r-l+1;
    cout<<cnt<<endl;
    return 0;
}

Compilation message (stderr)

strange_device.cpp: In function 'int main()':
strange_device.cpp:46:18: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   46 |     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