Fortunate numbers: Difference between revisions

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+</pre>
+=={{header|C++}}==
+<syntaxhighlight lang="c++">
+#include <algorithm>
+#include <cstdint>
+#include <iostream>
+#include <set>
+#include <vector>
+std::vector<int32_t> prime_numbers(const int32_t& limit) {
+	const int32_t half_limit = ( limit % 2 == 0 ) ? limit / 2 : 1 + limit / 2;
+	std::vector<bool> composite(half_limit, false);
+	for ( int32_t i = 1, p = 3; i < half_limit; p += 2, ++i ) {
+		if ( ! composite[i] ) {
+			for ( int32_t a = i + p; a < half_limit; a += p ) {
+				composite[a] = true;
+			}
+		}
+	}
+	std::vector<int32_t> primes{2};
+	for ( int32_t i = 1, p = 3; i < half_limit; p += 2, ++i ) {
+		if ( ! composite[i] ) {
+			primes.push_back(p);
+		}
+	}
+	return primes;
+}
+bool contains(const std::vector<int32_t>& list, const int32_t& n) {
+	return std::find(list.begin(), list.end(), n) != list.end();
+}
+int main() {
+	std::vector<int32_t> primes = prime_numbers(250'000'000);
+	std::set<int32_t> fortunates;
+	int32_t primorial = 1;
+	int32_t index = 0;
+	while ( fortunates.size() < 8 ) {
+		primorial *= primes[index++];
+		int32_t candidate = 3;
+		while ( ! contains(primes, primorial + candidate) ) {
+			candidate += 2;
+		}
+		fortunates.emplace(candidate);
+	}
+	std::cout << "The first 8 distinct fortunate numbers are:" << std::endl;
+	for ( const int32_t& fortunate : fortunates ) {
+		std::cout << fortunate << " ";
+	}
+}
+<syntaxhighlight>
+<pre>
+The first 8 distinct fortunate numbers are:
+5 7 13 17 19 23 37
 </pre>