Points

#include <cstdio>
#include <algorithm>

const int maxN = 10000;
const int mod = 666013;

int N;
class Point
{
public:
  int x, y;
  Point(int _x = 0, int _y = 0):
    x(_x), y(_y) { }
  inline bool operator < (const Point& other) const {
    return (x == other.x) ? (y > other.y) : (x < other.x);
  }
} p[maxN + 1];

int d[maxN + 1];

int main()
{
  freopen("points.in", "r", stdin);
  freopen("points.out", "w", stdout);
  scanf("%d", &N);

  for(int i = 1; i <= N; ++ i)
    scanf("%d %d", &p[i].x, &p[i].y);

  std :: sort(p + 1, p + N + 1);
  d[1] = 1;
  for(int i = 2; i <= N; ++ i)
  {
    d[i] = 1;
    for(int j = i - 1; j > 0; -- j)
      if(p[j].y >= p[i].y)
        d[i] = (d[i] + d[j]) % mod;
  }

  int Ans = 0;
  for(int i = 1; i <= N; ++ i)
    Ans = (Ans + d[i]) % mod;
  printf("%d\n", Ans);
  return 0;
}