Submission #933754

#	Time	Username	Problem	Language	Result	Execution time	Memory
933754		irmuun	Strange Device (APIO19_strange_device)	C++17	100 / 100	418 ms	71472 KiB

strange_device

#include<bits/stdc++.h>
 
using namespace std;
 
#define ll long long
#define pb push_back
#define ff first
#define ss second
#define all(s) s.begin(),s.end()
#define rall(s) s.rbegin(),s.rend()

int main(){
    ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
    ll n,a,b;
    cin>>n>>a>>b;
    ll l[n+5],r[n+5];
    ll g=a/gcd((b+1)%a,a),MX=1e18+1;
    if(MX/b>=g){
        g=g*b;
    }
    else{
        g=MX;
    }
    for(ll i=1;i<=n;i++){
        cin>>l[i]>>r[i];
    }
    vector<pair<ll,ll>>v;
    for(ll i=1;i<=n;i++){
        if(r[i]-l[i]+1>=g){
            cout<<g;
            return 0;
        }
        ll L=l[i]%g,R=r[i]%g;
        if(L<=R){
            v.pb({L,R});
        }
        else{
            v.pb({0,R});
            v.pb({L,g-1});
        }
    }
    sort(all(v));
    ll ans=0;
    for(ll i=0;i<v.size();){
        ll nxt=i,curR=v[i].ss;
        while(nxt+1<v.size()&&v[nxt+1].ff<=curR){
            nxt++;
            curR=max(curR,v[nxt].ss);
        }
        ans+=curR-v[i].ff+1;
        i=nxt+1;
    }
    cout<<ans;
}

Compilation message (stderr)

strange_device.cpp: In function 'int main()':
strange_device.cpp:44:17: 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]
   44 |     for(ll i=0;i<v.size();){
      |                ~^~~~~~~~~
strange_device.cpp:46:20: 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 |         while(nxt+1<v.size()&&v[nxt+1].ff<=curR){
      |               ~~~~~^~~~~~~~~

• 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