#!/usr/bin/perl 
open IFILE,"<sst.dat";
open PFILE,">sst.ppm";

$mxv=-100.;
$mnv=100.;
$h=0;
#read data file once to find min and max:
while ($aline=<IFILE>){
	next if $aline=~m/^#/;
	@vals=split /\s+/,$aline;
	$h++;
	foreach $v (@vals){
		next if $v>9999;
		$mxv=$v if $v>$mxv;
		$mnv=$v if $v<$mnv;
	}
}
$w=@vals;
close IFILE ;
print "min value=$mnv   max value=$mxv  width=$w  height=$h\n";
$sc=255./($mxv-$mnv);

#print header use P3 for ascii, P6 for binary:
print PFILE "P6
$w $h
255
";

#read data file again to assign colors: 
open IFILE,"<sst.dat";
while ($aline=<IFILE>){
	next if $aline=~m/^#/;
	@vals=split /\s+/,$aline;
	foreach $v (@vals){
		if ($v>9999){
			($r,$g,$b)=(0,0,0);
		}
		else{
#STUDENTS: fix the following three lines to assign colors to the $v:
#(hint: you may want to use the value of $sc to help you)
			$g=int 0.;
			$r=int 255.;
			$b=int 0.;
		}
		#print PFILE "$r $g $b\n"; #use with P3
	    print PFILE pack("c",$r),pack("c",$g),pack("c",$b); #use with P6
	}
}
close PFILE;
print "file sst.ppm was written\n";