#!/usr/bin/perl


$var1 ="Mahanakorn University";
print" \$var1=$var1\n\n";
$var1="10";
$var2="20";
$var3=$var1+$var2;
print"\$var1=$var1\n\n";
print"\$var1=$var2\n\n";
print"$var1+$var2=$var3";