atcoder#ABC168E. [ABC168E] ∙ (Bullet)

[ABC168E] ∙ (Bullet)

Score: 500500 points

Problem Statement

We have caught NN sardines. The deliciousness and fragrantness of the ii-th sardine is AiA_i and BiB_i, respectively.

We will choose one or more of these sardines and put them into a cooler. However, two sardines on bad terms cannot be chosen at the same time.

The ii-th and jj-th sardines (ij)(i \neq j) are on bad terms if and only if AiAj+BiBj=0A_i \cdot A_j + B_i \cdot B_j = 0.

In how many ways can we choose the set of sardines to put into the cooler? Since the count can be enormous, print it modulo 10000000071000000007.

Constraints

  • All values in input are integers.
  • 1N2×1051 \leq N \leq 2 \times 10^5
  • 1018Ai,Bi1018-10^{18} \leq A_i, B_i \leq 10^{18}

Input

Input is given from Standard Input in the following format:

NN

A1A_1 B1B_1

::

ANA_N BNB_N

Output

Print the count modulo 10000000071000000007.

3
1 2
-1 1
2 -1
5

There are five ways to choose the set of sardines, as follows:

  • The 11-st
  • The 11-st and 22-nd
  • The 22-nd
  • The 22-nd and 33-rd
  • The 33-rd
10
3 2
3 2
-1 1
2 -1
-3 -9
-8 12
7 7
8 1
8 2
8 4
479