In bioinformatics, long character strings are often encoded in a format called FASTA.

A FASTA file can contain several strings, each identified by a name marked by a > (greater than) character at the beginning of the line.



Task

Write a program that reads a FASTA file such as:

>Rosetta_Example_1
THERECANBENOSPACE
>Rosetta_Example_2
THERECANBESEVERAL
LINESBUTTHEYALLMUST
BECONCATENATED


Output:
Rosetta_Example_1: THERECANBENOSPACE
Rosetta_Example_2: THERECANBESEVERALLINESBUTTHEYALLMUSTBECONCATENATED

Note that a high-quality implementation will not hold the entire file in memory at once; real FASTA files can be multiple gigabytes in size.




proc fastaReader {filename} {
    set f [open $filename]
    set sep ""
    while {[gets $f line] >= 0} {
	if {[string match >* $line]} {
	    puts -nonewline "$sep[string range $line 1 end]: "
	    set sep "\n"
	} else {
	    puts -nonewline $line
	}
    }
    puts ""
    close $f
}
 
fastaReader ./rosettacode.fas