from math import sqrt
N = 10000000
cnt = 0
x = []
y = []
M = 0
for _ in range(N):
    x1 = uniform(0,2)
    y1 = uniform(0,2)
    x2 = uniform(0,2)
    y2 = uniform(0,2)
    if (x2 - 1)**2 + (y2 - 1)**2 <= 1 and (x1 - 1)**2 + (y1 - 1)**2 <= 1:
        M += 1
        if sqrt((x2 - x1)**2 + (y2 - y1)**2) < 1:
            cnt += 1

print(cnt / M)