{"trustable":true,"prependHtml":"\u003cstyle type\u003d\u0027text/css\u0027\u003e\n .input, .output {\n border: 1px solid #888888;\n }\n .output {\n margin-bottom: 1em;\n position: relative;\n top: -1px;\n }\n .output pre, .input pre {\n background-color: #EFEFEF;\n line-height: 1.25em;\n margin: 0;\n padding: 0.25em;\n }\n \u003c/style\u003e\n \u003clink rel\u003d\"stylesheet\" href\u003d\"//codeforces.org/s/96598/css/problem-statement.css\" type\u003d\"text/css\" /\u003e\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$$\u0027]]\n }\n });\n\u003c/script\u003e\n\u003cscript type\u003d\"text/javascript\" async src\u003d\"https://mathjax.codeforces.org/MathJax.js?config\u003dTeX-AMS_HTML-full\"\u003e\u003c/script\u003e","sections":[{"title":"","value":{"format":"HTML","content":"\u003cp\u003eYou are given an array consisting of $$$n$$$ integers $$$a_1, a_2, \\dots , a_n$$$ and an integer $$$x$$$. It is guaranteed that for every $$$i$$$, $$$1 \\le a_i \\le x$$$.\u003c/p\u003e\u003cp\u003eLet\u0027s denote a function $$$f(l, r)$$$ which erases all values such that $$$l \\le a_i \\le r$$$ from the array $$$a$$$ and returns the resulting array. For example, if $$$a \u003d [4, 1, 1, 4, 5, 2, 4, 3]$$$, then $$$f(2, 4) \u003d [1, 1, 5]$$$.\u003c/p\u003e\u003cp\u003eYour task is to calculate the number of pairs $$$(l, r)$$$ such that $$$1 \\le l \\le r \\le x$$$ and $$$f(l, r)$$$ is sorted in non-descending order. Note that the empty array is also considered sorted.\u003c/p\u003e"}},{"title":"Input","value":{"format":"HTML","content":"\u003cp\u003eThe first line contains two integers $$$n$$$ and $$$x$$$ ($$$1 \\le n, x \\le 10^6$$$) — the length of array $$$a$$$ and the upper limit for its elements, respectively.\u003c/p\u003e\u003cp\u003eThe second line contains $$$n$$$ integers $$$a_1, a_2, \\dots a_n$$$ ($$$1 \\le a_i \\le x$$$).\u003c/p\u003e"}},{"title":"Output","value":{"format":"HTML","content":"\u003cp\u003ePrint the number of pairs $$$1 \\le l \\le r \\le x$$$ such that $$$f(l, r)$$$ is sorted in non-descending order.\u003c/p\u003e"}},{"title":"Examples","value":{"format":"HTML","content":"\u003ctable class\u003d\u0027vjudge_sample\u0027\u003e\n\u003cthead\u003e\n \u003ctr\u003e\n \u003cth\u003eInput\u003c/th\u003e\n \u003cth\u003eOutput\u003c/th\u003e\n \u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\u003cpre\u003e3 3\n2 3 1\n\u003c/pre\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cpre\u003e4\n\u003c/pre\u003e\u003c/td\u003e\n \u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n"}},{"title":"","value":{"format":"HTML","content":"\u003ctable class\u003d\u0027vjudge_sample\u0027\u003e\n\u003cthead\u003e\n \u003ctr\u003e\n \u003cth\u003eInput\u003c/th\u003e\n \u003cth\u003eOutput\u003c/th\u003e\n \u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\u003cpre\u003e7 4\n1 3 1 2 2 4 3\n\u003c/pre\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cpre\u003e6\n\u003c/pre\u003e\u003c/td\u003e\n \u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n"}},{"title":"Note","value":{"format":"HTML","content":"\u003cp\u003eIn the first test case correct pairs are $$$(1, 1)$$$, $$$(1, 2)$$$, $$$(1, 3)$$$ and $$$(2, 3)$$$.\u003c/p\u003e\u003cp\u003eIn the second test case correct pairs are $$$(1, 3)$$$, $$$(1, 4)$$$, $$$(2, 3)$$$, $$$(2, 4)$$$, $$$(3, 3)$$$ and $$$(3, 4)$$$.\u003c/p\u003e"}}]}