If you are going to use a for loop, I'd use something along the lines of ... 
my $keys = "5    10    14    16    17    20    25    26    38  1  42  
+  47    54";
my $substr = '1';
print "\nExist" if $_ eq $substr for split /\s+/, $keys;

[download]
Having said that, the OP has the whiff of homework

A user level that continues to overstate my experience :-))

In reply to Re: Foreach loop by Bloodnok
in thread Foreach loop by PetreAdi

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