Problem:
Distance

Write a program which calculates the distance between two points P1(x1, y1) and P2(x2, y2).

Input

Four real numbers x1, y1, x2 and y2 are given in a line.

Output

Print the distance in real number. The output should not contain an absolute error greater than 10-4.

Sample Input

0 0 1 1

Sample Output

1.41421356

Solution in Python3 (judge verdict: Accepted)

import math

def distance(a, b):
    dx = abs(a[0]-b[0])
    dy = abs(a[1]-b[1])
    return math.sqrt(dx*dx + dy*dy)

if __name__ == '__main__':
    x1, y1, x2, y2 = map(float, input().split())
    print(distance((x1, y1), (x2, y2)))