{"trustable":true,"prependHtml":"\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 async src\u003d\"https://mathjax.codeforces.org/MathJax.js?config\u003dTeX-AMS-MML_HTMLorMML\" type\u003d\"text/javascript\"\u003e\u003c/script\u003e","sections":[{"title":"","value":{"format":"HTML","content":"\u003cdiv class\u003d\"panel_content\"\u003eAlice and Bob are playing game. Firstly, Alice drew a regular polygon with n vertices, then assigned each vertex a number.\u003cbr\u003eThen Bob\u0027s goal is to change all the numbers to non-negative numbers. He can do following operation in each step: choose one vertex i, supposed Ai is the number on vertex i, then add Ai to it\u0027s left and right adjacent vertex, and turn Ai into -Ai.\u003cbr\u003eNow you are to help Bob to find out the minimum step to reach his goal.\u003cbr\u003e\u003c/div\u003e"}},{"title":"Input","value":{"format":"HTML","content":"Multiple test cases ended with EOF.\u003cbr\u003eEach test case begins with one integer n, followed a line consist of by n integers representing the numbers on the vertices clockwise.\u003cbr\u003e\u003cbr\u003e2\u0026lt;n≤10\u003csup\u003e5\u003c/sup\u003e\u003cbr\u003e|Ai| ≤ 10\u003csup\u003e5\u003c/sup\u003e\u003cbr\u003e|sum{Ai}| ≤ 10\u003cbr\u003e"}},{"title":"Output","value":{"format":"HTML","content":"If Bob cannot end this game, then output \u0027Endless\u0027(without quotes), otherwise output the minimum step for Bob to end this game."}},{"title":"Sample","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\r\n1 -2 3\r\n\u003c/pre\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cpre\u003e2\u003c/pre\u003e\u003c/td\u003e\n \u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n"}},{"title":"Hint","value":{"format":"HTML","content":"In the sample, first turn -2 to 2, then the sequences became -1 2 1,\u003cbr\u003e then choose -1, the result is 1 1 0, all the numbers are non-negative, so the minimum step would be 2."}}]}