Dutch national flag problem: Difference between revisions

Content added Content deleted
m (→‎{{header|AppleScript}}: Tabs -> 4spaces)
(Rename Perl 6 -> Raku, alphabetize, minor clean-up)
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Non-sorted: rbwww
Non-sorted: rbwww
Sorted: rwwwb</pre>
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#}}==
=={{header|C_sharp|C#}}==
<lang csharp>using System;
<lang csharp>using System;
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}
}
</lang>
</lang>

=={{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|Ceylon}}==
=={{header|Ceylon}}==
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Is sorted: true
Is sorted: true
</pre>
</pre>




=={{header|Julia}}==
=={{header|Julia}}==
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are_ordered($balls) or die "Incorrect\n";</lang>
are_ordered($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.
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|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|Phix}}==
=={{header|Phix}}==
Line 2,692: Line 2,628:
==> OK
==> OK
</pre>
</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}}==
=={{header|REXX}}==
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</pre>
</pre>

=={{header|Ring}}==
=={{header|Ring}}==
<lang ring>
<lang ring>
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