{"trustable":true,"sections":[{"title":"","value":{"format":"HTML","content":"\u003cimg src\u003d\"CDN_BASE_URL/1ceed47c2f908291e1fdbca819024ec0?v\u003d1714350897\" border\u003d\"0\" alt\u003d\"Problem illustration\" align\u003d\"RIGHT\" class\u003d\"problem_raimage\"\u003e\u003cdiv class\u003d\"problem_par\"\u003e\u003cdiv class\u003d\"problem_par_normal\"\u003eEnt Fedya\u0027s birthday was coming up, and his friends made a birthday cake \r\nfor him. They didn\u0027t know how many candles they should put on the cake \r\nbecause nobody remembered Fedya\u0027s age. That is why they just put a very \r\nlarge number of candles on the cake. When Ent Sasha saw the cake, he got \r\nangry because he had a very good memory and knew that Fedya would become \r\n\u003ci\u003ek\u003c/i\u003e years of age. Happily, there were \u003ci\u003en\u003c/i\u003e \u0026gt; \u003ci\u003ek\u003c/i\u003e candles on the cake. Since \r\nFedya\u0027s age became known, the ents decided to cut from the cake a convex \r\npolygonal piece of nonzero area that would contain exactly \u003ci\u003ek\u003c/i\u003e candles \r\n(counting the cakes inside the piece and on its boundary). \u003c/div\u003e\u003c/div\u003e\u003cdiv class\u003d\"problem_par\"\u003e\u003cdiv class\u003d\"problem_par_normal\"\u003eThe cake is a 2 · 10\u003csup\u003e9\u003c/sup\u003e × 2 · 10\u003csup\u003e9\u003c/sup\u003e mm square. The distance \r\nfrom each candle to each side of the square is a positive integer number \r\nof millimeters. \u003c/div\u003e\u003c/div\u003e"}},{"title":"Input","value":{"format":"HTML","content":"\u003cdiv class\u003d\"problem_par\"\u003e\u003cdiv class\u003d\"problem_par_normal\"\u003eThe first line contains the integers \u003ci\u003en\u003c/i\u003e and \u003ci\u003ek\u003c/i\u003e (1 ≤ \u003ci\u003ek\u003c/i\u003e \u0026lt; \u003ci\u003en\u003c/i\u003e ≤ \r\n1\u0026nbsp;000). In the following \u003ci\u003en\u003c/i\u003e lines you are given pairs of integers, \r\nwhich are the coordinates of the candles. The origin of coordinates is at \r\nthe center of the cake and the coordinate axes are parallel to its sides. \r\nAll the coordinates are strictly less than\u0026nbsp;10\u003csup\u003e9\u003c/sup\u003e in absolute value. It is \r\nguaranteed that no two candles are at the same point. \u003c/div\u003e\u003c/div\u003e"}},{"title":"Output","value":{"format":"HTML","content":"\u003cdiv class\u003d\"problem_par\"\u003e\u003cdiv class\u003d\"problem_par_normal\"\u003eIn the first line output the number \u003ci\u003em\u003c/i\u003e of vertices of the polygon that \r\nshould be cut from the cake (3 ≤ \u003ci\u003em\u003c/i\u003e ≤ 10\u0026nbsp;000). In the following \u003ci\u003em\u003c/i\u003e \r\nlines give the coordinates of the vertices ordered counterclockwise. The \r\ncoordinates must be integers not exceeding\u0026nbsp;10\u003csup\u003e9\u003c/sup\u003e in absolute value. The \r\nangles at the vertices must not be straight. The lengths of all sides must \r\nbe positive. If there are several solutions, output any of them. It is \r\nguaranteed that there exists at least one solution satisfying the above \r\nconstraints. \u003c/div\u003e\u003c/div\u003e"}},{"title":"Sample","value":{"format":"HTML","content":"\u003ctable class\u003d\u0027vjudge_sample\u0027\u003e\n\u003cthead\u003e\n \u003ctr\u003e\n \u003cth\u003eInput\u003c/th\u003e\n \u003cth\u003eOutput\u003c/th\u003e\n \u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\u003cpre\u003e5 3\r\n1 0\r\n1 2\r\n2 1\r\n3 0\r\n3 2\r\n\u003c/pre\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cpre\u003e3\r\n1 0\r\n2 1\r\n1 2\r\n\u003c/pre\u003e\u003c/td\u003e\n \u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n"}}]}