{"trustable":true,"prependHtml":"\u003cscript\u003e window.katexOptions \u003d { disable: true }; \u003c/script\u003e\n\u003cscript type\u003d\"text/x-mathjax-config\"\u003e\n MathJax.Hub.Config({\n tex2jax: {\n inlineMath: [[\u0027$$$\u0027,\u0027$$$\u0027], [\u0027$\u0027,\u0027$\u0027]],\n displayMath: [[\u0027$$$$$$\u0027,\u0027$$$$$$\u0027], [\u0027$$\u0027,\u0027$$\u0027]]\n }\n });\n\u003c/script\u003e\n\u003cscript async src\u003d\"https://mathjax.codeforces.org/MathJax.js?config\u003dTeX-AMS-MML_HTMLorMML\" type\u003d\"text/javascript\"\u003e\u003c/script\u003e","sections":[{"title":"","value":{"format":"HTML","content":"\u003cdiv class\u003d\"panel_content\"\u003eNow here is a matrix with letter \u0027a\u0027,\u0027b\u0027,\u0027c\u0027,\u0027w\u0027,\u0027x\u0027,\u0027y\u0027,\u0027z\u0027 and you can change \u0027w\u0027 to \u0027a\u0027 or \u0027b\u0027, change \u0027x\u0027 to \u0027b\u0027 or \u0027c\u0027, change \u0027y\u0027 to \u0027a\u0027 or \u0027c\u0027, and change \u0027z\u0027 to \u0027a\u0027, \u0027b\u0027 or \u0027c\u0027. After you changed it, what\u0027s the largest submatrix with the same letters you can make?\u003c/div\u003e"}},{"title":"Input","value":{"format":"HTML","content":"The input contains multiple test cases. Each test case begins with m and n (1 ≤ m, n ≤ 1000) on line. Then come the elements of a matrix in row-major order on m lines each with n letters. The input ends once EOF is met."}},{"title":"Output","value":{"format":"HTML","content":"For each test case, output one line containing the number of elements of the largest submatrix of all same letters."}},{"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 4\r\nabcw\r\nwxyz\r\n\u003c/pre\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cpre\u003e3\r\n\u003c/pre\u003e\u003c/td\u003e\n \u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n"}}]}