{"trustable":true,"sections":[{"title":"","value":{"format":"HTML","content":"\u003cp\u003eGiven a \u003ci\u003em\u003c/i\u003e-by-\u003ci\u003en\u003c/i\u003e (0,1)-matrix, of all its submatrices of all 1’s which is the largest? By \u003ci\u003elargest\u003c/i\u003e we mean that the submatrix has the most elements.\u003c/p\u003e"}},{"title":"Input","value":{"format":"HTML","content":"\u003cp\u003eThe input contains multiple test cases. Each test case begins with \u003ci\u003em\u003c/i\u003e and \u003ci\u003en\u003c/i\u003e (1 ≤ \u003ci\u003em\u003c/i\u003e, \u003ci\u003en\u003c/i\u003e ≤ 2000) on line. Then come the elements of a (0,1)-matrix in row-major order on \u003ci\u003em\u003c/i\u003e lines each with \u003ci\u003en\u003c/i\u003e numbers. The input ends once EOF is met.\u003c/p\u003e"}},{"title":"Output","value":{"format":"HTML","content":"\u003cp\u003eFor each test case, output one line containing the number of elements of the largest submatrix of all 1’s. If the given matrix is of all 0’s, output 0.\u003c/p\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\u003e2 2\r\n0 0\r\n0 0\r\n4 4\r\n0 0 0 0\r\n0 1 1 0\r\n0 1 1 0\r\n0 0 0 0\u003c/pre\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cpre\u003e0\r\n4\u003c/pre\u003e\u003c/td\u003e\n \u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n"}}]}