-----Input-----

The first line contains a single integer n (1 ≤ n ≤ 1000) — the number of points on a plane.

Each of the next n lines contains two real coordinates x_{i} and y_{i} of the $i^{\text{th}}$ point, specified with exactly 2 fractional digits. All coordinates are between  - 1000 and 1000, inclusive.


-----Output-----

Output a single real number θ — the answer to the problem statement. The absolute or relative error of your answer should be at most 10^{ - 2}.


-----Examples-----
Input
8
-2.14 2.06
-1.14 2.04
-2.16 1.46
-2.14 0.70
-1.42 0.40
-0.94 -0.48
-1.42 -1.28
-2.16 -1.62

Output
5.410

Input
5
2.26 1.44
2.28 0.64
2.30 -0.30
1.58 0.66
3.24 0.66

Output
5.620

Input
8
6.98 2.06
6.40 1.12
5.98 0.24
5.54 -0.60
7.16 0.30
7.82 1.24
8.34 0.24
8.74 -0.76

Output
5.480

Input
5
10.44 2.06
10.90 0.80
11.48 -0.48
12.06 0.76
12.54 2.06

Output
6.040

Input
8
16.94 2.42
15.72 2.38
14.82 1.58
14.88 0.50
15.76 -0.16
16.86 -0.20
17.00 0.88
16.40 0.92

Output
6.040

Input
7
20.62 3.00
21.06 2.28
21.56 1.36
21.66 0.56
21.64 -0.52
22.14 2.32
22.62 3.04

Output
6.720

Source: codeforces | Difficulty: HARD
Tags: Geometry


Solutions:
n = int(input())
print(sum([float(input().split()[1]) for i in range(n)]) / n + 5)


n = int(input())
s = 0.0
for i in range(0, n):
	data = input().split()
	(x, y) = (float(data[0]), float(data[1]))
	s += y
print('%.3f' % (5 + s / n))


n = int(input())
P = [[float(x) for x in input().split()] for _ in range(n)]
print(5 + sum((b for (a, b) in P)) / n)


n = int(input())
ab = 0
for i in range(n):
	(x, y) = map(float, input().split())
	ab += y
print(5 + ab / n)


n = int(input())
theta = 5.0
for i in range(n):
	theta += list(map(float, input().split()))[1] / n
print('%.3f' % theta)


import sys

def solve():
	n = int(input())
	avg = sum([list(map(float, input().split()))[1] for _ in range(n)]) / n
	return avg + 5
if sys.hexversion == 50594544:
	sys.stdin = open('test.txt')
print(solve())


(n, num) = (int(input()), 0)
for i in range(n):
	num += float(input().split()[1])
print(f'{num / n + 5:.3f}')


s = 0
n = int(input())
for i in range(n):
	(x, y) = list(map(float, input().split()))
	s += y
print(s / n + 5)


class InputHandlerObject(object):
	inputs = []

	def getInput(self, n=0):
		res = ''
		inputs = self.inputs
		if not inputs:
			inputs.extend(input().split(' '))
		if n == 0:
			res = inputs[:]
			inputs[:] = []
		while n > len(inputs):
			inputs.extend(input().split(' '))
		if n > 0:
			res = inputs[:n]
			inputs[:n] = []
		return res
InputHandler = InputHandlerObject()
g = InputHandler.getInput
n = int(input())
sum = 0
for i in range(n):
	(nx, ny) = g()
	sum += float(ny)
print(5 + sum / n)


a = int(input())
s = 0
for i in range(a):
	s += float(input().split()[1])
d = round(s / a, 3) + 5
l = len(str(d).split('.')[1])
if l < 3:
	print(str(d) + '0' * (3 - l))
else:
	print(d)