Submission #372476

#	Time	Username	Problem	Language	Result	Execution time	Memory
372476		hivakarami	Strange Device (APIO19_strange_device)	C++14	100 / 100	551 ms	53700 KiB

strange_device

#include<bits/stdc++.h>
 
using namespace std;
 
typedef long long int ll;
typedef long double ld;
#define f first
#define s second
 
const int N = 1e6 + 100;
const ll mod = 1e9 + 7;
const ll inf = 1e18 + 10;

vector<pair<ll, ll>> v;

int main()
{
    ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);
	
	int n;
	ll a, b;
	cin >> n >> a >> b;
	ll k = a / __gcd(a, b+1);
	if(k > inf/b)
		k = inf;
	else
		k *= b;
	
	//cout << k << endl;
	
	while(n--)
	{
		ll l, r;
		cin >> l >> r;
		
		if(r - l + 1 >= k)
		{
			cout << k << endl;
			return 0;
		}
		
		l = l%k;
		r = r%k;
		
		if(l <= r)
		{
			v.push_back({l, r});
		}
		else
		{
			v.push_back({l, k-1});
			v.push_back({0, r});
		}
		
	}
	
	sort(v.begin(), v.end());
	
	ll ans = 0, mx = -1;
	
	for(int i = 0; i < v.size(); i++)
	{
		ll l = v[i].f, r = v[i].s;
		
		//cout << l << ' ' << r << endl; 
		
		if(l > mx)
			ans += r - l + 1;
		else if(r >= mx)
			ans += r - mx;
		mx = max(mx, r);	
	}
	
	cout << ans << endl;
	
    return 0;
}


 

Compilation message (stderr)

strange_device.cpp: In function 'int main()':
strange_device.cpp:61:19: 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]
   61 |  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