Submission #729694

#	Time	Username	Problem	Language	Result	Execution time	Memory
729694		danikoynov	Strange Device (APIO19_strange_device)	C++14	5 / 100	5068 ms	48948 KiB

strange_device

#include<bits/stdc++.h>
#define endl '\n'

using namespace std;
typedef long long ll;

void speed()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
}

const int maxn = 1e6 + 10;

int n;
ll l[maxn], r[maxn];
ll A, B;

struct point
{
    ll x, t;
    point(ll _x = 0, ll _t = 0)
    {
        x = _x;
        t = _t;
    }

    bool operator < (const point &p) const
    {
        if (x == p.x)
            return t < p.t;
        return x < p.x;
    }
};


vector < point > vec;
void add_segment(int l, int r)
{

    vec.push_back(point(l, 1));
    vec.push_back(point(r, -1));
}
void solve()
{
    cin >> n >> A >> B;

    for (int i = 1; i <= n; i ++)
    {
        cin >> l[i] >> r[i];
    }
    ll g = __gcd(A, B + 1);
    /// period is A * B / g
    if ((double)(1e18) / (double)(A) < (double)(B) / (double)(g))
    {
        while(true);
        ll ans = 0;
        for (int i = 1; i <= n; i ++)
        {
            ans = ans + (r[i] - l[i] + 1);
        }
        cout << ans << endl;
        return;
    }

    long long period = (A / g) * B;
    for (int i = 1; i <= n; i ++)
    {


            if (r[i] - l[i] + 1 >= period)
            {
                cout << period << endl;
                return;
            }

            r[i] ++;
            ll x = l[i] % period, y = r[i] % period;
            if (x <= y)
            {
                add_segment(x, y);
            }
            else
            {
                add_segment(0, y);
                add_segment(x, period);
            }

    }

    sort(vec.begin(), vec.end());
    ll ans = 0, cnt = 0;
    for (int i = 0; i < vec.size();)
    {
        int r = i;
        while(r < vec.size() && vec[i].x == vec[r].x)
            r ++;
        for (int j = i; j < r; j ++)
            cnt += vec[j].t;
            //cout << i << " : " << r << " " << cnt << " " << vec[r].x << " " << vec[i].x << endl;
        if (cnt > 0)
            ans = ans + vec[r].x - vec[i].x;
        i = r;
    }
    cout << ans << endl;
}


int main()
{
    solve();
    return 0;
}
/**
1  10000 3312452154131231
1 1
*/

Compilation message (stderr)

strange_device.cpp: In function 'void solve()':
strange_device.cpp:94:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<point>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   94 |     for (int i = 0; i < vec.size();)
      |                     ~~^~~~~~~~~~~~
strange_device.cpp:97:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<point>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   97 |         while(r < vec.size() && vec[i].x == vec[r].x)
      |               ~~^~~~~~~~~~~~

• Subtask 1: 0 / 10
• Subtask 2: 0 / 5
• Subtask 3: 5 / 5
• Subtask 4: 0 / 5
• Subtask 5: 0 / 5
• Subtask 6: 0 / 20
• Subtask 7: 0 / 20
• Subtask 8: 0 / 30