#AT1593. E - ∙ (Bullet)
E - ∙ (Bullet)
E - ∙ (Bullet)
Score: $500$ points
Problem Statement
We have caught $N$ sardines. The deliciousness and fragrantness of the $i$-th sardine is $A_i$ and $B_i$, 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 $i$-th and $j$-th sardines $(i \neq j)$ are on bad terms if and only if $A_i \cdot A_j + B_i \cdot B_j = 0$.
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 $1000000007$.
Constraints
- All values in input are integers.
- $1 \leq N \leq 2 \times 10^5$
- $-10^{18} \leq A_i, B_i \leq 10^{18}$
Input
Input is given from Standard Input in the following format:
Output
Print the count modulo $1000000007$.
3
1 2
-1 1
2 -1
5
There are five ways to choose the set of sardines, as follows:
- The $1$-st
- The $1$-st and $2$-nd
- The $2$-nd
- The $2$-nd and $3$-rd
- The $3$-rd
10
3 2
3 2
-1 1
2 -1
-3 -9
-8 12
7 7
8 1
8 2
8 4
479