{"raw_statement":[{"iden":"problem statement","content":"You have a pot and $N$ ingredients. Each ingredient has a real number parameter called _value_, and the value of the $i$\\-th ingredient $(1 \\leq i \\leq N)$ is $v_i$.\nWhen you put two ingredients in the pot, they will vanish and result in the formation of a new ingredient. The value of the new ingredient will be $(x + y) / 2$ where $x$ and $y$ are the values of the ingredients consumed, and you can put this ingredient again in the pot.\nAfter you compose ingredients in this way $N-1$ times, you will end up with one ingredient. Find the maximum possible value of this ingredient."},{"iden":"constraints","content":"*   $2 \\leq N \\leq 50$\n*   $1 \\leq v_i \\leq 1000$\n*   All values in input are integers."},{"iden":"input","content":"Input is given from Standard Input in the following format:\n\n$N$\n$v_1$ $v_2$ $\\ldots$ $v_N$"},{"iden":"sample input 1","content":"2\n3 4"},{"iden":"sample output 1","content":"3.5\n\nIf you start with two ingredients, the only choice is to put both of them in the pot. The value of the ingredient resulting from the ingredients of values $3$ and $4$ is $(3 + 4) / 2 = 3.5$.\nPrinting `3.50001`, `3.49999`, and so on will also be accepted."},{"iden":"sample input 2","content":"3\n500 300 200"},{"iden":"sample output 2","content":"375\n\nYou start with three ingredients this time, and you can choose what to use in the first composition. There are three possible choices:\n\n*   Use the ingredients of values $500$ and $300$ to produce an ingredient of value $(500 + 300) / 2 = 400$. The next composition will use this ingredient and the ingredient of value $200$, resulting in an ingredient of value $(400 + 200) / 2 = 300$.\n*   Use the ingredients of values $500$ and $200$ to produce an ingredient of value $(500 + 200) / 2 = 350$. The next composition will use this ingredient and the ingredient of value $300$, resulting in an ingredient of value $(350 + 300) / 2 = 325$.\n*   Use the ingredients of values $300$ and $200$ to produce an ingredient of value $(300 + 200) / 2 = 250$. The next composition will use this ingredient and the ingredient of value $500$, resulting in an ingredient of value $(250 + 500) / 2 = 375$.\n\nThus, the maximum possible value of the last ingredient remaining is $375$.\nPrinting `375.0` and so on will also be accepted."},{"iden":"sample input 3","content":"5\n138 138 138 138 138"},{"iden":"sample output 3","content":"138"}],"translated_statement":null,"sample_group":[],"show_order":["default"],"formal_statement":null,"simple_statement":null,"has_page_source":true}