Submission #834079

#	Time	Username	Problem	Language	Result	Execution time	Memory
834079		Antekb	Strange Device (APIO19_strange_device)	C++17	100 / 100	1267 ms	69040 KiB

strange_device

#include<bits/stdc++.h>
#define st first
#define nd second
#define all(x) (x).begin(), (x).end()
#define pb push_back
#define eb emplace_back
#define pp pop_back
#define mp make_pair
using namespace std;
using pii = pair<int, int>;
using ll = long long;
using vi = vector<int>;
using vii = vector<pii>;
void debug(){cerr<<"\n";}
template<typename H, typename... T>
void debug(H h, T... t){
	cerr<<h;
	if(sizeof...(t)){
		cerr<<", ";
	}
	debug(t...);
}
#define deb(x...) cerr<<#x<<" = ";debug(x);

mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());

int main(){
	int n;
	ll a, b;
	cin>>n>>a>>b;
	if(b>=ll(1e18)/(a/gcd(a, b+1))){
		ll s=0;
		for(int i=0; i<n; i++){
			ll l, r;
			cin>>l>>r;
			s+=r-l+1;
		}
		cout<<s;
		return 0;
	}
	ll t=b*(a/__gcd(a, b+1));
	vector<pair<ll, int> > V;
	for(int i=0; i<n; i++){
		ll l, r;
		cin>>l>>r;
		if(r-l+1>=t){
			cout<<t;
			return 0;
		}
		l%=t;
		r%=t;
		if(l<=r){
			V.eb(l, 1);
			V.eb(r+1, -1);
		}
		else{
			V.eb(0, 1);
			V.eb(r+1, -1);
			V.eb(l, 1);
		}
	}
	V.eb(t, 0);
	sort(all(V));
	ll s=0, prv=0;
	int part=0;
	for(auto i:V){
		if(i.st!=prv){
			if(part>0)s+=i.st-prv;
			prv=i.st;
		}
		part+=i.nd;
	}
	cout<<s;
}

• 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