1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
|
///
/// @file count_primes1.cpp
/// @brief Count the primes up to 10^9.
///
/// Copyright (C) 2022 Kim Walisch, <kim.walisch@gmail.com>
///
/// This file is distributed under the BSD License. See the COPYING
/// file in the top level directory.
///
#include <primesieve/ParallelSieve.hpp>
#include <primesieve/pod_vector.hpp>
#include <stdint.h>
#include <cmath>
#include <cstdlib>
#include <iostream>
#include <iomanip>
using namespace primesieve;
/// Correct pi(x) values to compare with test results
const pod_array<uint64_t, 9> pix =
{
4, // pi(10^1)
25, // pi(10^2)
168, // pi(10^3)
1229, // pi(10^4)
9592, // pi(10^5)
78498, // pi(10^6)
664579, // pi(10^7)
5761455, // pi(10^8)
50847534 // pi(10^9)
};
void check(bool OK)
{
std::cout << " " << (OK ? "OK" : "ERROR") << "\n";
if (!OK)
std::exit(1);
}
int main()
{
std::cout << std::left;
ParallelSieve ps;
ps.setStart(0);
ps.setStop(0);
uint64_t count = 0;
// pi(x) with x = 10^(i+1)
for (size_t i = 0; i < pix.size(); i++)
{
count += ps.countPrimes(ps.getStop() + 1, (uint64_t) std::pow(10.0, i + 1));
std::cout << "pi(10^" << i + 1 << ") = " << std::setw(12) << count;
check(count == pix[i]);
}
// Test PreSieve with bufferPrimes < 100.
// The thread interval must be sufficiently large
// otherwise minimal pre-sieving is used.
// Using a single thread increases thread interval.
ps.setNumThreads(1);
count = ps.countPrimes(0, (uint64_t) std::pow(10.0, 9));
std::cout << "pi(10^9) = " << std::setw(12) << count;
check(count == 50847534);
std::cout << std::endl;
std::cout << "All tests passed successfully!" << std::endl;
return 0;
}
|
