{"trustable":false,"sections":[{"title":"","value":{"format":"HTML","content":"\u003chtml\u003e\n \u003chead\u003e\u003c/head\u003e\n \u003cbody\u003e\n \u003cdiv id\u003d\"problem-body\"\u003e \n \u003cp\u003e\n There is a quadrilateral shape such that the opposite sides are equal. To each side of the quadrilateral there is a square, meaning four squares in total. The coordinates of the centers of two such squares adjacent to two opposite sides of the quadrilateral are given. Find the coordinates of the two centers of the other two squares.\u003c/p\u003e\n \n \u003ch3\u003eInput Specification\u003c/h3\u003e \n \u003cp\u003eThe input consists of multiple lines. Each line has four floating point numbers \u003cem\u003ex_1, y_1, x_2, y_2. (x_1, y_1)\u003c/em\u003e is the coordinates of one given centre, while \u003cem\u003e(x_2, y_2)\u003c/em\u003e is the coordinates of the other. Input is terminated by end of file.\n\u003c/p\u003e\n \u003ch3\u003eOutput Specification\u003c/h3\u003e \n \u003cp\u003eIf the other two centers cannot be determined then print \u003cem\u003e\"Impossible\"\u003c/em\u003e without the quotes. Otherwise, print \u003cem\u003ex_3, y_3, x_4, y_4\u003c/em\u003e separated by spaces where \u003cem\u003e(x_3, y_3)\u003c/em\u003e and \u003cem\u003e(x_4, y_4)\u003c/em\u003e are the coordinates of the other two centers. The coordinates must be floating point numbers and they must have \u003cem\u003e10\u003c/em\u003e digits after the decimal point.\u003c/p\u003e \n \u003ch3\u003eExample\u003c/h3\u003e \n \u003cpre\u003e\u003cstrong\u003eInput:\u003c/strong\u003e\n10 0 -10 0\n10 0 -10 0\n10 0 -10 0\n\n\u003cstrong\u003eOutput:\u003c/strong\u003e\n0.0000000000 10.0000000000 0.0000000000 -10.0000000000\n0.0000000000 10.0000000000 -0.0000000000 -10.0000000000\n0.0000000000 -10.0000000000 0.0000000000 10.0000000000\n\u003c/pre\u003e \n \u003c/div\u003e\n \u003c/body\u003e\n\u003c/html\u003e"}}]}