{"trustable":false,"sections":[{"title":"","value":{"format":"HTML","content":"\u003cstyle type\u003d\"text/css\"\u003eh1,h2,h3,h4,h5,h6{margin-bottom:0;}div.textBG p{margin: 0 0 0.0001pt;}\u003c/style\u003e\u003c!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\"\u003e\r\n\u003chtml\u003e\r\n\u003chead\u003e\r\n\u003ctitle\u003e\r\nTIUP June 2005 - Problem D\r\n\u003c/title\u003e\r\n\u003cmeta http-equiv\u003d\"Content-Type\" content\u003d\"text/html; charset\u003diso-8859-1\"\u003e\r\n\u003c/head\u003e\r\n\r\n\u003cbody\u003e\r\n\r\n\u003ch1\u003eSafe Salutations\u003c/h1\u003e\r\n\r\n\u003ch2\u003eProblem\u003c/h2\u003e\r\n\r\n\u003cp\u003e\r\nAs any minimally superstitious person knows all too well, terrible\r\nthings will happen when four persons do a crossed handshake.\r\n\u003c/p\u003e\r\n\u003cp\u003e\r\nYou, an intrepid computer scientist, are given the task of easing the\r\nburden of these people by providing them with the feasible set of\r\nhandshakes that include everyone in the group while avoiding any such\r\ncrossings. The following figure illustrates the case for 3 pairs of\r\npersons:\r\n\u003c/p\u003e\r\n\u003cimg width\u003d75% src\u003d\"http://uva.onlinejudge.org/external/9/991.gif\"\u003e\r\n\r\n\u003ch2\u003eInput\u003c/h2\u003e\r\n\u003cp\u003e\r\nThe input to this problem contains several datasets separated by a blank line. Each dataset is simply an integer \u003ci\u003en\u003c/i\u003e, the number of\r\n\u003cb\u003epairs\u003c/b\u003e of people in the group, with 1 \u0026le; \u003ci\u003en\u003c/i\u003e \u0026le; 10.\r\n\u003c/p\u003e\r\n\r\n\r\n\u003ch2\u003eOutput\u003c/h2\u003e\r\n\u003cp\u003e\r\nThe output is equally simple. For each dataset, print a single integer indicating the number\r\nof possible crossless handshakes that involve everyone in a group\r\nwith \u003ci\u003en\u003c/i\u003e pairs of people. Print a blank line between datasets.\r\n\u003c/p\u003e\r\n\r\n\r\n\u003ch2\u003eSample Input\u003c/h2\u003e\r\n\r\n\u003cpre\u003e\r\n4\r\n\u003c/pre\u003e\r\n\r\n\u003ch2\u003eSample Output\u003c/h2\u003e\r\n\r\n\u003cpre\u003e\r\n14\r\n\u003c/pre\u003e\r\n\r\n\u003c/html\u003e"}}]}