32 lines
459 B
C++
32 lines
459 B
C++
#include "sieve.h"
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namespace sieve {
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using namespace std;
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primes_t primes(size_t n)
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{
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primes_t result;
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vector<char> sieve(n, false);
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for (size_t p = 2, p2 = 2*2; p2 < n; ++p, p2 = p*p) {
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if (sieve[p])
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continue;
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for (size_t i = p2; i < n; i += p) {
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sieve[i] = true;
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}
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}
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for (size_t i = 2; i < n; ++i)
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if (!sieve[i])
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result.push_back(i);
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return result;
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}
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}
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