{"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":"HTML","content":"AVM is an archer. AVM is taking a match of archer with Malfple. They try to shoot in the target in turns, and AVM shoots first. The probability of shooting the target each time is \u003ci\u003ea\u003c/i\u003e/\u003ci\u003eb\u003c/i\u003e for AVM while \u003ci\u003ec\u003c/i\u003e/\u003ci\u003ed\u003c/i\u003e for Malfple. The one who shoots in the target first should be the winner.\u003cbr\u003e\u003cbr\u003e\n\nOutput the probability that AVM will win the match."}},{"title":"Input","value":{"format":"HTML","content":"A single line contains four integers \u003ci\u003ea\u003c/i\u003e, \u003ci\u003eb\u003c/i\u003e, \u003ci\u003ec\u003c/i\u003e, \u003ci\u003ed\u003c/i\u003e (1 \u003c\u003d \u003ci\u003ea\u003c/i\u003e, \u003ci\u003eb\u003c/i\u003e, \u003ci\u003ec\u003c/i\u003e, \u003ci\u003ed\u003c/i\u003e \u003c\u003d 1000, \u0026nbsp; 0 \u0026lt; \u003ci\u003ea\u003c/i\u003e/\u003ci\u003eb\u003c/i\u003e \u0026lt; 1, \u0026nbsp; 0 \u0026lt; \u003ci\u003ec\u003c/i\u003e/\u003ci\u003ed\u003c/i\u003e \u0026lt; 1)"}},{"title":"Output","value":{"format":"HTML","content":"Print a single real number, the probability that AVM will win the match.\u003cbr\u003e\u003cbr\u003e\n\nThe answer will be considered correct if the absolute or relative error doesn\u0027t exceed 10\u003csup\u003e- 6\u003c/sup\u003e."}},{"title":"Examples","value":{"format":"HTML","content":"\u003ctable border\u003d\"1px solid\" width\u003d\"100%\" cellpadding\u003d\"4px\" cellspacing\u003d\"0px\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003cth width\u003d\"50%\"\u003eSample Input\u003c/th\u003e\n \u003cth width\u003d\"50%\"\u003eSample Output\u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign\u003d\"top\"\u003e\u003ccode\u003e\n1 2 1 2\u003cbr\u003e\n \u003cbr\u003e\u003c/code\u003e\u003c/td\u003e\n \u003ctd valign\u003d\"top\"\u003e\u003ccode\u003e\n0.666666666667\u003cbr\u003e\n \u003cbr\u003e\u003c/code\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e"}}]}