Longest string challenge: Difference between revisions

{{out}}

<pre>ccc

ddd

ggg</pre>

=={{header|Nim}}==

To compare the length of strings, we could have use the standard function "cmp" but it would have been cheating. We could also have used the trick based on exception catching, but, in Nim, IndexError is considered as a defect and, even if in current version (1.4) IndexError is actually catchable, it would probably not still be the case in future versions.

So, we have used another way to compare the length of strings, clearly not efficient, but efficiency is not a goal here.

<lang Nim>import strutils

const

# Define int constants instead of an enum to use only ints and strings.

Shorter = -1

SameLength = 0

Longer = 1

type LengthComparison = range[Shorter..Longer]

func cmpLength(a, b: string): LengthComparison =

let a = repeat(' ', a.len)

let b = repeat(' ', b.len)

result = if a in b: (if b in a: SameLength else: Shorter) else: Longer

var longest = ""

var result = ""

for line in "longest_string_challenge.txt".lines:

case cmpLength(line, longest)

of Shorter:

discard

of SameLength:

result.add '\n' & line

of Longer:

longest = line

result = line

echo result</lang>