deletions | additions       diff --git a/Introduction.tex b/Introduction.tex  index 7833b15..9c78c89 100644  --- a/Introduction.tex  +++ b/Introduction.tex 
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\url{http://web.archive.org/web/20140715223826/http://bendwavy.org/sphere.htm}  \subsection{Restatement of the Problem}  The problem is that the Gamma Knife radiosurgery can be inaccurate and when it is inaccurate, it can bear dangerous consequences, namely harming healthy brain tissue.\begin{lstlisting}[language=python]  tumor_length = randint(int(0.1 * matrix.area), int(0.9 * matrix.area))  coord = [randint(1, matrix.m), random.randint(1, matrix.n)]  for i in range(0, matrix.tumor_length):  direction = randint(1, 4)  if direction == UP:  coord[1] -= 1  elif direction == DOWN:  coord[1] += 1  elif direction == LEFT:  coord[0] -= 1  elif direction == RIGHT:  coord[0] += 1  \end{lstlisting}