{"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\n\u003cscript\u003e\n window.katexOptions \u003d {\n delimiters: [\n {left: \u0027$$$$$$\u0027, right: \u0027$$$$$$\u0027, display: true},\n {left: \u0027$$$\u0027, right: \u0027$$$\u0027, display: false},\n {left: \u0027$$\u0027, right: \u0027$$\u0027, display: true},\n {left: \u0027$\u0027, right: \u0027$\u0027, display: false}\n ]\n };\n\u003c/script\u003e\n","sections":[{"title":"","value":{"format":"HTML","content":"\u003cp\u003eSuppose, oneday the government of AjobDesh decided to impose TAX on \u003cem\u003eLaughing\u003c/em\u003e and this TAX should be paid immediately on the spot. If you want to laugh \u003cspan class\u003d\"tex-span\"\u003e\u003ci\u003ew\u003c/i\u003e\u003c/span\u003e times, you have to pay \u003cspan class\u003d\"tex-span\"\u003e\u003ci\u003ek\u003c/i\u003e\u003c/span\u003e taka for the first laugh, \u003cspan class\u003d\"tex-span\"\u003e2\u003ci\u003ek\u003c/i\u003e\u003c/span\u003e taka for the second one and so on (in other words, you have to pay \u003cspan class\u003d\"tex-span\"\u003e\u003ci\u003ei\u003c/i\u003e·\u003ci\u003ek\u003c/i\u003e\u003c/span\u003e taka for the \u003cspan class\u003d\"tex-span\"\u003e\u003ci\u003ei\u003c/i\u003e\u003c/span\u003e-th laugh). \u003c/p\u003e\n\u003cp\u003eYou have \u003cspan class\u003d\"tex-span\"\u003e\u003ci\u003en\u003c/i\u003e\u003c/span\u003e taka. Unfortunately, you forgot about this imposed TAX and laughed \u003ci\u003ew\u003c/i\u003e time. Now, you have to borrow some money from your friend. How many taka do you have to borrow from your friend to pay the imposed TAX for laughing \u003cspan class\u003d\"tex-span\"\u003e\u003ci\u003ew\u003c/i\u003e\u003c/span\u003e times?\u003c/p\u003e"}},{"title":"Input","value":{"format":"HTML","content":"\u003cp\u003eThe first line contains three positive integers \u003cspan class\u003d\"tex-span\"\u003e\u003ci\u003ek\u003c/i\u003e, \u003ci\u003en\u003c/i\u003e, \u003ci\u003ew\u003c/i\u003e\u003c/span\u003e (\u003cspan class\u003d\"tex-span\"\u003e1 ≤ \u003ci\u003ek\u003c/i\u003e, \u003ci\u003ew\u003c/i\u003e ≤ 1000\u003c/span\u003e, \u003cspan class\u003d\"tex-span\"\u003e0 ≤ \u003ci\u003en\u003c/i\u003e ≤ 10\u003csup class\u003d\"upper-index\"\u003e9\u003c/sup\u003e\u003c/span\u003e), the cost of the first laugh, initial number of taka you have and the number of laugh you made. \u003c/p\u003e"}},{"title":"Output","value":{"format":"HTML","content":"\u003cp\u003eOutput one integer — the amount of taka that you must borrow from your friend. If you don\u0027t have to borrow money, output \u003cspan class\u003d\"tex-span\"\u003e0\u003c/span\u003e.\u003c/p\u003e"}},{"title":"Sample 1","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 17 4\n\u003c/pre\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cpre\u003e13\u003c/pre\u003e\u003c/td\u003e\n \u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n"}}]}