The following calculates the sum efficiently (sum(1..N) = N(N+1)/2), yet finds a legitimately use for foreach: 

foreach my $n (@ARGV) { print($n*($n+1)/2, "\n"); }

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In reply to Re: How do I write a program that calculates the sum of all numbers to a number, n? by ikegami
in thread How do I write a program that calculates the sum of all numbers to a number, n? by fmny94

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