Caffeine Levels

A half$-$life is the amount of time it takes for a substance or entity to fall to half its original value. Caffeine has a half$-$life of about $6$ hours in humans. Given caffeine amount $($in $mg)$ as input, output the caffeine level after $6,12,$ and $24$ hours. Use a string formatting expression with conversion specifiers to output the caffeine amount as floating$-$point numbers.

Output each fioating$-$point value with two digits after the decimal point, which can be achieved as follows: print$($ffyour$\_$value:$2$ff$)$

Example:

Input

$100$

Output

After $6$ hours: $50\mathrm{.}00mg$

After $12$ hours: $25\mathrm{.}00mg$

After $24$ hours: $6\mathrm{.}25mg$

Note: A cup of coffee has about $100mg.$ A soda has about $40mg.$ An "energy" drink $($a misnomer$)$ has between $100mg$ and $200mg.$