Primes whose sum of digits is 25: Difference between revisions

=={{header|Zig}}==

{{trans|Nim}}

<syntaxhighlight lang="zig">const std = @import("std");</syntaxhighlight>

<syntaxhighlight lang="zig">fn isPrime(n: u64) bool {

if (n < 2) return false;

if (n % 2 == 0) return n == 2;

if (n % 3 == 0) return n == 3;

var d: u64 = 5;

while (d * d <= n) {

if (n % d == 0) return false;

d += 2;

if (n % d == 0) return false;

d += 4;

}

return true;

}</syntaxhighlight>

<syntaxhighlight lang="zig">fn digitSum(n_: u64) u16 {

var n = n_; // parameters are immutable, copy to var

var sum: u16 = 0;

while (n != 0) {

sum += @truncate(u16, n % 10);

n /= 10;

}

return sum;

}</syntaxhighlight>

<syntaxhighlight lang="zig">pub fn main() !void {

var arena = std.heap.ArenaAllocator.init(std.heap.page_allocator);

defer arena.deinit();

var result = std.ArrayList(u64).init(arena.allocator());

defer result.deinit();

{

var n: u64 = 3;

while (n <= 5000) : (n += 2)

if (digitSum(n) == 25 and isPrime(n))

try result.append(n);

}

const stdout = std.io.getStdOut().writer();

for (result.items, 0..) |n, i|

_ = try stdout.print("{d:4}{s}", .{ n, if ((i + 1) % 6 == 0) "\n" else " " });

}</syntaxhighlight>

{{out}}

<pre> 997 1699 1789 1879 1987 2689

2797 2887 3499 3697 3769 3877

3967 4597 4759 4957 4993</pre>