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\usepackage{longtable}
\usepackage{dcolumn}
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\newcommand{\mc}[1]{\multicolumn{1}{c}{#1}}
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\begin{document}
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\begin{longtable}{*{10}{.}}
\caption[Opt]{Table1\label{L10}} \\\hline
  \multicolumn{1}{|c|}{Path}
      & \multicolumn{3}{c||}{Para1} & \multicolumn{3}{c||}{Para2}
      & \multicolumn{3}{c|}{Para3} \\\cline{2-10}
  \multicolumn{1}{|c|}{No.}
     & \mc{A} & \mc{B} & \mc{C} & \mc{D} & \mc{E} & \mc{F} & \mc{G} & \mc{H}
	 & \multicolumn{1}{c|}{I} \\\hline\hline
\endfirsthead
\multicolumn{10}{r}{\textsl{continued on next page $\ldots$}} \\
\endfoot
\hline \hline
  \multicolumn{10}{|c|}{Iteration1: 1} \\
  \multicolumn{10}{|c|}{Iteration2: 3} \\
\hline
\endlastfoot
  1 & $243.69$ & $0.21$ & $0.23$ & $+42.44$ & $0.04$ & $0.01$ & $-31.18$ &
$0.18$ & $0.16$ \\\hline
  2 & $402.25$ & $0.12$ & $0.11$ & $+23.75$ & $0.12$ & $0.09$ & $-35.18$ &
$0.34$ & $0.32$ \\\hline
  3 & $665.44$ & $2.34$ & $0.89$ & $-41.90$ & $0.70$ & $1.55$ & $-37.72$ &
$2.07$ & $1.87$ \\\hline
  4 & $545.02$ & $0.15$ & $0.13$ & $-23.67$ & $0.14$ & $0.13$ & $-37.95$ &
$0.19$ & $0.20$
\end{longtable}

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\end{document}
