#include

#include

#include

using namespace std;

double ConvertWeight$($double value, char inUnits, char outUnits$)\{$

const double PT$\_$TO$\_$L $=0\mathrm{.}473167$;

const double QT$\_$TO$\_$L $=0\mathrm{.}94633$;

const double GAL$\_$TO$\_$L $=3\mathrm{.}78541$;

if $($inUnits $==\text{'}$P$\text{'}$ && outUnits $==\text{'}$L$\text{'})\{$

return value $*$ PT$\_$TO$\_$L;

$\}$ else if $($inUnits $==\text{'}$Q$\text{'}$ && outUnits $==\text{'}$L$\text{'})\{$

return value $*$ QT$\_$TO$\_$L;

$\}$ else if $($inUnits $==\text{'}$G$\text{'}$ && outUnits $==\text{'}$L$\text{'})\{$

return value $*$ GAL$\_$TO$\_$L;

$\}$ else $\{$

cerr $<<$ "Invalid input or output units." $<<$ endl;

return $-1\mathrm{.}0$; $//$ Error value

$\}$

$\}$

int main$()\{$

ifstream inputFile$("$data$.$txt$")$;

if $(!$inputFile.is$\_$open$())\{$

cerr $<<$ "Unable to open the file." $<<$ endl;

return $1$;

$\}$

double value;

char inUnits, outUnits;

while $($inputFile $>>$ value $>>$ inUnits $>>$ outUnits$)\{$

double result $=$ ConvertWeight$($value$,$ inUnits, outUnits$)$;

if $($result $!=-1\mathrm{.}0)\{$

cout $<<$ fixed $<<$ setprecision$(6)$;

cout $<<$ value $<<""<<$ inUnits $<<"$ is equal to $"<<$ result $<<""<<$ outUnits $<<$ endl;

$\}$

$\}$

inputFile.close$()$;

return $0$;

$\}$