Blank compact discs are on sale in packages of three kinds. A package with $100$ disсs costs $100$ UAH, one with $20$ discs costs $30$ UAH, and one disс costs $2$ UAH. What minimal sum of money should you pay to buy $n$ such disсs? \InputFile The natural number $n$ ($n$ ≤ $1000$). \OutputFile Print the minimal sum to buy $n$ disсs. .