Middle three digits: Difference between revisions
→{{header|Ruby}}: Add code.
(→{{header|Rust}}: Add Ruby header.) |
(→{{header|Ruby}}: Add code.) |
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Line 548:
=={{header|Ruby}}==
<lang>def middle_three_digits(n)
# minus sign doesn't factor into digit count,
# and calling #abs acts as a duck-type assertion
n = n.abs
# convert to string and find length
l = (s = n.to_s).length
# check validity
raise "Number must have at least three digits" if l < 3
raise "Number must have an odd number of digits" if l % 2 == 0
return s[l/2-1,3].to_i
end
[ 123, 12345, 1234567, 987654321, 10001, -10001, -123, -100, 100, -12345,
1, 2, -1, -10, 2002, -2002, 0 ].each do |n|
print "#{n}: "
begin
puts "%03d" % middle_three_digits(n)
rescue RuntimeError => e
puts e.to_s
end
end</lang>
123: 123
12345: 234
1234567: 345
987654321: 654
10001: 000
-10001: 000
-123: 123
-100: 100
100: 100
-12345: 234
1: Number must have at least three digits
2: Number must have at least three digits
-1: Number must have at least three digits
-10: Number must have at least three digits
2002: Number must have an odd number of digits
-2002: Number must have an odd number of digits
0: Number must have at least three digits</pre>
Output:
<pre>
=={{header|Rust}}==
<lang rust>fn middle_three_digits(x: int) -> Result<~str, ~str> {
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