Hi -- I'm working on writing code to check each string within an array. This is directed at checking that a DNA input contains only A, T, C, and G. I have written it such that you can input your DNA sequence on the command line. When I run this with an input such as "ATGTCAHCGT," I get nothing back where I should get a print statement of "Non-nucleotide at 6 position." What I am missing/ where am I going wrong? Any help much appreciated. Cheers, A

my $dna_input = $ARGV[0]; # turn command line input into a variable

my @dna = split("", $dna_input); #split the variable into an array so 
+as to check each nucleotide

my $count = 0; # keep track of position so as to report where there is
+ a non-nuceloetide character
my $base;
foreach $base (@dna) {
        if($base eq 'A' || 'T' || 'C' || 'G') {
                $count += 1;
                }
        else {
                 print "Non-nucleotide at $count position\n";
                }
}

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In reply to If/else within a foreach loop to check strings within an array by Anonymous Monk

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