{"trustable":false,"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":"MD","content":"因为白学姐太热爱公平,在每一场比赛之中,都给大家发了巨额红包,这让钱包本来就空空的白学姐哭了出来,只能去商店打(mai)工(shen)\n\n学姐所在的商店在假期中营业 n 天。每天出售的商品数已经确定,第 i 天出售 ki 件商品,有 li 个客户会来购买。已知每个客户恰好购买一件商品。如果没有商品可以购买,那客户就会选择空手离开。\n\n为了让商店赚更多的钱,学姐要进行促销,她可以选择 f 天将出售的商品数翻倍,但是客户的数量不会翻倍。让你算算学姐一共能卖出多少件商品。"}},{"title":"Input","value":{"format":"MD","content":"第一行包含两个整数 n 和 f (1 ≤ n ≤ 10^5, 0 ≤ f ≤ n)表示销售天数和促销的天数。\n之后 n 行每行两个整数 ki, li (0 ≤ ki, li ≤ 10^9) 表示第 i 天销售的商品数和第 i 天来的客户数。"}},{"title":"Output","value":{"format":"MD","content":"\u003cdiv class\u003d\"output-specification\"\u003e\n \u003cdiv class\u003d\"section-title\"/div\u003e\n \u003cp\u003e输出最多能销售的商品数。\u003c/p\u003e\n\u003c/div\u003e"}},{"title":"Example","value":{"format":"MD","content":"\u003cstyle type\u003d\u0027text/css\u0027\u003e .input, .output {border: 1px solid #888888;} .output {margin-bottom:1em;position:relative;top:-1px;} .output pre,.input pre {background-color:#EFEFEF;line-height:1.25em;margin:0;padding:0.25em;} .title {background-color:#FFFFFF;border-bottom: 1px solid #888888;font-family:arial;font-weight:bold;padding:0.25em;} \u003c/style\u003e\u003cdiv class\u003d\"sample-tests\"\u003e\n \u003cdiv class\u003d\"section-title\"/div\u003e\n \u003cdiv class\u003d\"sample-test\"\u003e\n \u003cdiv class\u003d\"input\"\u003e\n \u003cdiv class\u003d\"title\"\u003e\n Input\n \u003c/div\u003e\n \u003cpre\u003e4 2\u003cbr\u003e2 1\u003cbr\u003e3 5\u003cbr\u003e2 3\u003cbr\u003e1 5\u003cbr\u003e\u003c/pre\u003e\n \u003c/div\u003e\n \u003cdiv class\u003d\"output\"\u003e\n \u003cdiv class\u003d\"title\"\u003e\n Output\n \u003c/div\u003e\n \u003cpre\u003e10\u003c/pre\u003e\n \u003c/div\u003e\n \u003cdiv class\u003d\"input\"\u003e\n \u003cdiv class\u003d\"title\"\u003e\n Input\n \u003c/div\u003e\n \u003cpre\u003e4 1\u003cbr\u003e0 2\u003cbr\u003e0 3\u003cbr\u003e3 5\u003cbr\u003e0 6\u003cbr\u003e\u003c/pre\u003e\n \u003c/div\u003e\n \u003cdiv class\u003d\"output\"\u003e\n \u003cdiv class\u003d\"title\"\u003e\n Output\n \u003c/div\u003e\n \u003cpre\u003e5\u003c/pre\u003e\n \u003c/div\u003e\n \u003c/div\u003e\n\u003c/div\u003e"}},{"title":"Note","value":{"format":"MD","content":"\u003cdiv class\u003d\"note\"\u003e\n \u003cdiv class\u003d\"section-title\"Note/div\u003e\n \u003cp\u003e第一个样例翻倍第 \u003cspan class\u003d\"tex-span\"\u003e2\u003c/span\u003e 和第 \u003cspan class\u003d\"tex-span\"\u003e4\u003c/span\u003e 天。\u003c/p\u003e\n \u003cp\u003e第二个样例翻倍第 3 天。\u003c/p\u003e\n\u003c/div\u003e"}}]}