{"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\"\u003ePog and Szh are playing games.There is a sequence with $n$ numbers, Pog will choose a number A from the sequence. Szh will choose an another number named B from the rest in the sequence. Then the score will be $(A+B)$ mod $p$.They hope to get the largest score.And what is the largest score?\u003c/div\u003e"}},{"title":"Input","value":{"format":"HTML","content":"Several groups of data (no more than $5$ groups,$n \\geq 1000$).\u003cbr\u003e\u003cbr\u003eFor each case: \u003cbr\u003e\u003cbr\u003eThe following line contains two integers,$n(2 \\leq n \\leq 100000)$,$p(1 \\leq p \\leq 2^{31}-1)$。\u003cbr\u003e\u003cbr\u003eThe following line contains $n$ integers $a_i(0 \\leq a_i \\leq 2^{31}-1)$。"}},{"title":"Output","value":{"format":"HTML","content":"For each case,output an integer means the largest score."}},{"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\u003e4 4\r\n1 2 3 0\r\n4 4\r\n0 0 2 2\u003c/pre\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cpre\u003e3\r\n2\u003c/pre\u003e\u003c/td\u003e\n \u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n"}}]}