#! /usr/bin/perl
while (my $line = <>)
{
    if ($line =~ /SRC=\"([^\.]+)\.gif\"/)
    {
	my $basename = $1;
	my $file = "$basename.gif";
	$file = "$basename.png" if (-f "$basename.png");
	$file = "$basename.jpg" if (-f "$basename.jpg");
	$line =~ s/SRC=\"[^\.]+\.gif\"/SRC=\"$file\"/;
    }
    print $line;
}
exit 0;