Problem:
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:

N
A_1 B_1
:
A_N B_N

Output

Print the count modulo 1000000007.

Sample Input 1

3
1 2
-1 1
2 -1

Sample Output 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

Sample Input 2

10
3 2
3 2
-1 1
2 -1
-3 -9
-8 12
7 7
8 1
8 2
8 4

Sample Output 2

479

Solution in PyPy3 (7.3.0) (judge verdict: Wrong Answer)

# -*- coding: utf-8 -*-
from collections import Counter, defaultdict, deque
import math

import sys
# sys.setrecursionlimit(10**6)
# buff_readline = sys.stdin.buffer.readline
buff_readline = sys.stdin.readline
readline = sys.stdin.readline

INF = 2**62-1


def read_int():
    return int(buff_readline())


def read_int_n():
    return list(map(int, buff_readline().split()))


def read_float():
    return float(buff_readline())


def read_float_n():
    return list(map(float, buff_readline().split()))


def read_str():
    return readline().strip()


def read_str_n():
    return readline().strip().split()

def error_print(*args):
    print(*args, file=sys.stderr)


def mt(f):
    import time

    def wrap(*args, **kwargs):
        s = time.time()
        ret = f(*args, **kwargs)
        e = time.time()

        error_print(e - s, 'sec')
        return ret

    return wrap


from  fractions import Fraction

def frac(a, b):
    if a== 0 and b == 0:
        return (0, 0)
    if b == 0:
        return (1, 0)
    f = Fraction(a, b)
    a = f.numerator
    b = f.denominator
    return a, b


class Mod:
    def __init__(self, m):
        self.m = m

    def add(self, a, b):
        return (a + b) % self.m

    def sub(self, a, b):
        return (a - b) % self.m

    def mul(self, a, b):
        return ((a % self.m) * (b % self.m)) % self.m

    def div(self, a, b):
        return self.mul(a, pow(b, self.m-2, self.m))

    def pow(self, a, b):
        return pow(a, b, self.m)


@mt
def slv(N, AB):
    adb = Counter()
    for a, b in AB:
        a, b = frac(a, b)
        adb[(a, b)] += 1
    M = Mod(1000000007)
    ans = 1 + adb[(0, 0)]
    done = {(0, 0)}
    for k, v in adb.items():
        if k in done:
            continue
        a, b = k
        kk = frac(-b, a)
        n = adb[kk]
        done.add(k)
        done.add(kk)
        t = M.sub(M.pow(2, v) + M.pow(2, n), 1)
        ans = M.mul(ans, t)

    return M.sub(ans, 1)


def main():
    N = read_int()
    AB = [read_int_n() for _ in range(N)]
    print(slv(N, AB))


if __name__ == '__main__':
    main()