\begin{problem}{Bitqoins}{standard input}{standard output}{1 second}{256 megabytes}

Miss M lives on the planet Bitaqulandia, where the most popular currency is the bitqoin. 
Recently, Miss M held a mini-competition for friends, where each winner receives exactly three bitqoins.

It is known that in Miss M's competition, the prize fund is $n$ bitqoins, $m$ people won, and each winner receives exactly three bitqoins.

Determine how many bitqoins will remain with Miss M if she gives three bitqoins to each winner. It is known that Miss M has enough bitqoins.

\InputFile
The first line contains one integer $n$ ($3 \leq n \leq 100$) --- the number of bitqoins.

The second line contains one integer $m$ ($1 \leq m \leq 100$) --- the number of Miss M's friends who won in the competition.

It is guaranteed that Miss M will have enough bitqoins to distribute to her winning friends.

\OutputFile
Print a single integer --- the number of bitqoins that will remain with Miss M after she distributes them to the winners.

\Example

\begin{example}
\exmpfile{example.01}{example.01.a}%
\end{example}

\Note
Miss M had two friends win, she will give three bitqoins to each of them. In total, she will give away six, so only four bitqoins will remain.

\end{problem}

