{"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$$\u0027]]\n }\n });\n\u003c/script\u003e\n\u003cscript type\u003d\"text/javascript\" async src\u003d\"https://mathjax.codeforces.org/MathJax.js?config\u003dTeX-AMS_HTML-full\"\u003e\u003c/script\u003e","sections":[{"title":"","value":{"format":"HTML","content":"\u003cp\u003eYou have a playlist consisting of $$$n$$$ songs. The $$$i$$$-th song is characterized by two numbers $$$t_i$$$ and $$$b_i$$$ — its length and beauty respectively. The pleasure of listening to set of songs is equal to the total length of the songs in the set multiplied by the minimum beauty among them. For example, the pleasure of listening to a set of $$$3$$$ songs having lengths $$$[5, 7, 4]$$$ and beauty values $$$[11, 14, 6]$$$ is equal to $$$(5 + 7 + 4) \\cdot 6 \u003d 96$$$.\u003c/p\u003e\u003cp\u003eYou need to choose \u003cspan class\u003d\"tex-font-style-bf\"\u003eat most\u003c/span\u003e $$$k$$$ songs from your playlist, so the pleasure of listening to the set of these songs them is maximum possible.\u003c/p\u003e"}},{"title":"Input","value":{"format":"HTML","content":"\u003cp\u003eThe first line contains two integers $$$n$$$ and $$$k$$$ ($$$1 \\le k \\le n \\le 3 \\cdot 10^5$$$) – the number of songs in the playlist and the maximum number of songs you can choose, respectively.\u003c/p\u003e\u003cp\u003eEach of the next $$$n$$$ lines contains two integers $$$t_i$$$ and $$$b_i$$$ ($$$1 \\le t_i, b_i \\le 10^6$$$) — the length and beauty of $$$i$$$-th song.\u003c/p\u003e"}},{"title":"Output","value":{"format":"HTML","content":"\u003cp\u003ePrint one integer — the maximum pleasure you can get.\u003c/p\u003e"}},{"title":"Examples","value":{"format":"HTML","content":"\u003ctable class\u003d\u0027vjudge_sample\u0027\u003e\n\u003cthead\u003e\n \u003ctr\u003e\n \u003cth\u003eInput\u003c/th\u003e\n \u003cth\u003eOutput\u003c/th\u003e\n \u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\u003cpre\u003e4 3\n4 7\n15 1\n3 6\n6 8\n\u003c/pre\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cpre\u003e78\n\u003c/pre\u003e\u003c/td\u003e\n \u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n"}},{"title":"","value":{"format":"HTML","content":"\u003ctable class\u003d\u0027vjudge_sample\u0027\u003e\n\u003cthead\u003e\n \u003ctr\u003e\n \u003cth\u003eInput\u003c/th\u003e\n \u003cth\u003eOutput\u003c/th\u003e\n \u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\u003cpre\u003e5 3\n12 31\n112 4\n100 100\n13 55\n55 50\n\u003c/pre\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cpre\u003e10000\n\u003c/pre\u003e\u003c/td\u003e\n \u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n"}},{"title":"Note","value":{"format":"HTML","content":"\u003cp\u003eIn the first test case we can choose songs $$${1, 3, 4}$$$, so the total pleasure is $$$(4 + 3 + 6) \\cdot 6 \u003d 78$$$.\u003c/p\u003e\u003cp\u003eIn the second test case we can choose song $$$3$$$. The total pleasure will be equal to $$$100 \\cdot 100 \u003d 10000$$$.\u003c/p\u003e"}}]}