Dutch national flag problem: Difference between revisions
Rename Perl 6 -> Raku, alphabetize, minor clean-up
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Thundergnat (talk | contribs) (Rename Perl 6 -> Raku, alphabetize, minor clean-up) |
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Line 581:
Non-sorted: rbwww
Sorted: rwwwb</pre>
=={{header|C++}}==
<lang cpp>#include <algorithm>
#include <iostream>
// Dutch national flag problem
template <typename BidIt, typename T>
void dnf_partition(BidIt first, BidIt last, const T& low, const T& high)
{
for (BidIt next = first; next != last; ) {
if (*next < low) {
std::iter_swap(first++, next++);
} else if (!(*next < high)) {
std::iter_swap(next, --last);
} else {
++next;
}
}
}
enum Colors { RED, WHITE, BLUE };
void print(const Colors *balls, size_t size)
{
static const char *label[] = { "red", "white", "blue" };
std::cout << "Balls:";
for (size_t i = 0; i < size; ++i) {
std::cout << ' ' << label[balls[i]];
}
std::cout << "\nSorted: " << std::boolalpha << std::is_sorted(balls, balls + size) << '\n';
}
int main()
{
Colors balls[] = { RED, WHITE, BLUE, RED, WHITE, BLUE, RED, WHITE, BLUE };
std::random_shuffle(balls, balls + 9);
print(balls, 9);
dnf_partition(balls, balls + 9, WHITE, BLUE);
print(balls, 9);
}</lang>
{{out}}
<pre>
Balls: blue white red blue red blue white red white
Sorted: false
Balls: red red red white white white blue blue blue
Sorted: true
</pre>
=={{header|C_sharp|C#}}==
<lang csharp>using System;
Line 658 ⟶ 709:
}
</lang>
=={{header|Ceylon}}==
Line 1,856 ⟶ 1,857:
Is sorted: true
</pre>
=={{header|Julia}}==
Line 2,207 ⟶ 2,206:
are_ordered($balls) or die "Incorrect\n";</lang>
You can run it with no parameters, it sorts 10 balls in such a case. If you provide one parameter, it is used as the number of balls. The second parameter turns on debugging that shows how the balls are being swapped.
=={{header|Phix}}==
Line 2,692 ⟶ 2,628:
==> OK
</pre>
=={{header|Raku}}==
(formerly Perl 6)
Here are five ways to do it, all one liners (apart from the test apparatus).
<lang perl6>enum NL <red white blue>;
my @colors;
sub how'bout (&this-way) {
sub show {
say @colors;
say "Ordered: ", [<=] @colors;
}
@colors = NL.roll(20);
show;
this-way;
show;
say '';
}
say "Using functional sort";
how'bout { @colors = sort *.value, @colors }
say "Using in-place sort";
how'bout { @colors .= sort: *.value }
say "Using a Bag";
how'bout { @colors = flat red, white, blue Zxx bag(@colors».key)<red white blue> }
say "Using the classify method";
how'bout { @colors = flat (.list for %(@colors.classify: *.value){0,1,2}) }
say "Using multiple greps";
how'bout { @colors = flat (.grep(red), .grep(white), .grep(blue) given @colors) }</lang>
{{out}}
<pre>Using functional sort
red red white white red red red red red red red white red white red red red white white white
Ordered: False
red red red red red red red red red red red red red white white white white white white white
Ordered: True
Using in-place sort
red blue white red white blue white blue red white blue blue blue red white white red blue red blue
Ordered: False
red red red red red red white white white white white white blue blue blue blue blue blue blue blue
Ordered: True
Using a Bag
red blue blue blue white red white red white blue blue red red red red blue blue red white blue
Ordered: False
red red red red red red red red white white white white blue blue blue blue blue blue blue blue
Ordered: True
Using the classify method
blue red white blue blue white white red blue red red white red blue white white red blue red white
Ordered: False
red red red red red red red white white white white white white white blue blue blue blue blue blue
Ordered: True
Using multiple greps
red white blue white white red blue white red white red white white white white white red red blue red
Ordered: False
red red red red red red red white white white white white white white white white white blue blue blue
Ordered: True</pre>
=={{header|REXX}}==
Line 2,790:
</pre>
=={{header|Ring}}==
<lang ring>
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