File1:

Item,Time,Pattern ,Attributes,From
an_en11,200.00,{0 133},{ }
br_gh13,140.09,{0 59},{ }
ce_oy74,300.05,{0 230},{int_43}
dt_pp50,200.11,{0 122},{ }
er_tk02,305.47,{0 220},{ }
ef_yb41,200.05,{0 233},{ }

File2:

Item,Sink,Buffer,Cell,Slew,Path,Violation,Area 
dt_pp50,0,0,2,0.000,0.000,0,0.000
er_tk02,0,2,3,0.002,0.004,0,0.001
ef_yb41,0,1,5,0.000,0.000,0,0.000


Output :

Item,Sink,Buffer,Cell,Slew,Path,Violation,Area,Time
dt_pp50,0,0,2,0.000,0.000,0,0.000,200.11
er_tk02,0,2,3,0.002,0.004,0, 0.001,305.47
ef_yb41,0,1,5,0.000,0.000,0,0.000,200.05


##</code><code>##

 
my %file1Hash;
my $value4;
	
open my $file1, "<","design.rpt.csv" or die $!; 
open my $file2, "<","summary.rpt.csv"or die $!; 
open my $outfile_1, ">", "combined.rpt.csv" or die $!;
	
while(<$file1>){
		
	my($line) = $_; 
	chomp $line; 
	my($key,$value1,$value2,$value3) = $line =~ /(\w+),(\d+.\d+),(.\d+\s+\d+.\d+.)/g; 
	$value4 = "$value1,$value2,$value3,";
	push @{$file1Hash{$key}}, $value4; 
		} 
		
while(<$file2>){ 
		
	my ($line) = $_; 
	chomp $line; 
	my($key,$value1,$value2,$value3,$value4,$value5,$value6,$value7) = $line =~ /(\w+|\S+),(\d+),(\d+),(\d+),(\d+.\d+),(\d+.\d+),(\d+),(\d+.\d+)/g ; 
		
	if (exists $file1Hash{$key}) {
		
		print $file1Hash{$key}.",".$line."\n";
			
		    } 
	else {
		#  print $line."\n";
		    } 
} 

close $file1;
close $file2;
close $outfile_1;
	
exit 0;