granita - infoarena.ro

#include <fstream>
#include <algorithm>

using namespace std;

struct interval
{
    int x, y;
};
interval a[16005];

inline bool cmp(const interval A, const interval B)
{
    if (A.x == B.x)
        return A.y < B.y;
    return A.x < B.x;
}

int main()
{
    int n, i, cnt, x1, y1;
    ifstream fin("granita.in");
    fin >> n;
    for(i = 1; i <= n; i++)
        fin >> a[i].x >> a[i].y;
    sort(a + 1, a + n + 1, cmp);
    fin.close();
    cnt = 0;
    x1 = a[1].x;
    y1 = a[1].y;
    for(i = 2; i <= n; i++)
    {
        if(x1 < a[i].x && y1 > a[i].y) cnt++;
        else
        {
            x1 = a[i].x;
            y1 = a[i].y;
        }
    }
    ofstream fout("granita.out");
    fout << cnt << "\n";
    fout.close();
    return 0;
}