{"trustable":true,"prependHtml":"\u003cstyle type\u003d\"text/css\"\u003e\n #problem-body \u003e pre {\n display: block;\n padding: 9.5px;\n margin: 0 0 10px;\n font-size: 13px;\n line-height: 1.42857143;\n word-break: break-all;\n word-wrap: break-word;\n color: #333;\n background: rgba(255, 255, 255, 0.5);\n border: 1px solid #ccc;\n border-radius: 6px;\n }\n\u003c/style\u003e\n","sections":[{"title":"","value":{"format":"HTML","content":"\u003cdiv id\u003d\"problem-body\"\u003e\n\t\u003cp\u003eThe SUM problem can be formulated as follows: given four lists A, B, C, D of integer values, compute how many quadruplet (a, b, c, d ) belongs to A x B x C x D are such that a + b + c + d \u003d 0 . In the following, we assume that all lists have the same size n.\r\n\r\n\u003c/p\u003e\u003ch3\u003eInput\u003c/h3\u003e\r\n\u003cp\u003e\r\nThe first line of the input file contains the size of the lists n (this value can be as large as 4000). We then have n lines containing four integer values (with absolute value as large as 2\u003csup\u003e28\u003c/sup\u003e ) that belong respectively to A, B, C and D. \r\n\r\n\u003c/p\u003e\u003cp\u003e(\u003cb\u003eEdited: \u003c/b\u003en \u0026lt;\u003d 2500)\u003c/p\u003e\r\n\r\n\u003ch3\u003eOutput\u003c/h3\u003e\r\n\u003cp\u003eOutput should be printed on a single line.\r\n\u003c/p\u003e\u003ch3\u003eExample\u003c/h3\u003e\r\n\u003cdiv\u003e\u003ctable class\u003d\"vjudge_sample\"\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\u003e6\r\n-45 22 42 -16\r\n-41 -27 56 30\r\n-36 53 -37 77\r\n-36 30 -75 -46\r\n26 -38 -10 62\r\n-32 -54 -6 45\r\n\r\n\u003c/pre\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cpre\u003e5\r\n\u003c/pre\u003e\u003c/td\u003e\n \u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003c/div\u003e\r\n\n\u003c/div\u003e"}}]}