{"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":"MD","content":"Moogy owns a football stadium. Auoty wanted to rent the stadium for n hours. So Moogy told him that the i th hour cost i * k.\n\nFor example: If k is 20EGP and Moogy wants to play for 3 hours so the first hour will cost 1 x 20 and the second will cost 2 x 20 etc..\n\nMoogy has w EGP so he wants to know how much money he has to borrow to rent the the stadium for n hours. Moogy asked you to help him in this calculation.\n"}},{"title":"Input","value":{"format":"MD","content":"The first line contains three positive integers k, n, w (1 ≤ k, w ≤ 1000, 0 ≤ n ≤ 109), the cost of first hour, number of Egyptian pounds Moogy has and number of hours he wants to play."}},{"title":"Output","value":{"format":"MD","content":"\u003cp\u003eOutput one integer — the amount of Egyptian pounds that Moogy has to borrow. if he has enough money to pay for it, output 0."}},{"title":"Examples","value":{"format":"MD","content":"\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\u003e3 17 4\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\u003e13\u003c/pre\u003e\n \u003c/div\u003e\n\u003c/div\u003e"}}]}