using latex to write algorithm
\begin{program}
\mbox{A fast exponentiation procedure:}
\BEGIN \\ %
\FOR i:=1 \TO 10 \STEP 1 \DO
|expt|(2,i); \\ |newline|() \OD %
\rcomment{This text will be set flush to the right margin}
\WHERE
\PROC |expt|(x,n) \BODY
z:=1;
\DO \IF n=0 \THEN \EXIT \FI;
\DO \IF |odd|(n) \THEN \EXIT \FI;
\COMMENT{This is a comment statement};
n:=n/2; x:=x*x \OD;
\{ n>0 \};
n:=n-1; z:=z*x \OD;
|print|(z) \ENDPROC
\END
\end{program}