As you know, there are many strange planets in the universe. Dara and Sara are living in one of these strange planets with an unusual coordinate system. This Planet is like a grid having unit-sized cells with the houses considered as points placed in the center of cells. The cells are assigned a unique number as shown in figure 1. .. . 15 . . 14 6 16 . 13 5 1 7 17 24 12 4 0 2 8 18 23 11 3 9 19 . 22 10 20 . . 21 . .. Figure 1. The Strange Planet Recently, Dara and Sara have become familiar with the well-known Cartesian coordinate system based on X and Y axes, and would like to know the Euclidian distance between their houses. Unfor- tunately, they don’t know how to calculate this distance. So, they need your help to calculate it. You may assume that the cell with number 0 is located at the origin (with coordinate (0, 0)) of the Cartesian coordinate system. Input Input file consists of many test-cases. Each test-case consists of two integers 0 ≤ a, b ≤ 1, 000, 000, 000 indicating the cell numbers that contain their houses. The input will be terminated with a line con- taining two -1’s. Output For each test-case, print the Euclidian distance between the houses of Dara and Sara rounded to two digits after the fraction point. Sample Input 27 29 32 -1 -1 Sample Output 1.00 4.24