{"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$$\u0027]]\n }\n });\n\u003c/script\u003e\n\u003cscript type\u003d\"text/javascript\" async src\u003d\"https://mathjax.codeforces.org/MathJax.js?config\u003dTeX-AMS_HTML-full\"\u003e\u003c/script\u003e","sections":[{"title":"","value":{"format":"HTML","content":"\u003cp\u003eMiamiao writes a program and submits it to the judger. The judger tells her the result of each test case by a string containing \u003cspan class\u003d\"tex-font-style-tt\"\u003eP\u003c/span\u003e or \u003cspan class\u003d\"tex-font-style-tt\"\u003eF\u003c/span\u003e. \u003cspan class\u003d\"tex-font-style-tt\"\u003eP\u003c/span\u003e means to pass the test and \u003cspan class\u003d\"tex-font-style-tt\"\u003eF\u003c/span\u003e means to fail the test. Now Huihui wants to help her debug the program. He can remove the first or the last letter in $$$1$$$ minute or remove any other letter in $$$2$$$ minutes. After removing a letter from the middle the two remaining parts are joined.\u003c/p\u003e\u003cp\u003eNow, Huihui wants to know, how fast can he finish debugging the problem, which means he can obtain a string without any letter \u003cspan class\u003d\"tex-font-style-tt\"\u003eF\u003c/span\u003e?\u003c/p\u003e"}},{"title":"Input","value":{"format":"HTML","content":"\u003cp\u003eThe first line of input contains an integer $$$n(1 \\leq n \\leq 10^6)$$$, which means the length of the string.\u003c/p\u003e\u003cp\u003eThe second line of input contains a string $$$s(|s| \u003d n, s_i \\in \\{F, P\\})$$$, which means Miamiao\u0027s result.\u003c/p\u003e"}},{"title":"Output","value":{"format":"HTML","content":"\u003cp\u003eOutput a number, which means the minimum time needed to debug the problem by Huihui.\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\nFPPF\n\u003c/pre\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cpre\u003e2\n\u003c/pre\u003e\u003c/td\u003e\n \u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n"}}]}