# Prime number neighbors r = (2...100) # Nick Chapman 10/10/2006 primes = r.inject(r){|p, i| p.select{|n| n==i || n%i!=0}} twin_primes = primes.inject([]) do |t, n| n+2 == primes[primes.index(n)+1] ? t<<[n,n+2] : t end triplet_primes = pri…

a=(' '*80+"\n")*40 (x,y,c=split;a[y.to_i*81+x.to_i]=c.to_i)while gets a.each{|$_|puts$~if~/.*\S/} See Code Golf