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#include <sdsl/int_vector_buffer.hpp>
#include <string>
#include <iostream>
using namespace sdsl;
using namespace std;
int main(int argc, char* argv[])
{
if (argc < 1) {
cout << "Usage: " << argv[0] << endl;
cout << "(1) Writes an int_vector sequentially to a file" << endl;
cout << "(2) Streams the content from file" << endl;
cout << "(3) Remove the file" << endl;
return 1;
}
string tmp_file = "tmp_file.sdsl";
size_t size = 10000000;
std::mt19937_64 rng(13);
// (1) Writes an int_vector sequentially to the file tmp_file
{
// create an int_vector_buffer
int_vector_buffer<> ivb(tmp_file, // filename
std::ios::out, // we do not want to open an existing file, but create a new one
1024*1024, // use a buffer of about 1MB
64, // use 64bit for each integer
false); // use int_vector format
// write sequentially random values to disk
for (uint64_t i=0; i<size; ++i) {
ivb[i] = rng();
}
}
// (2) Streams the content of tmp_file
{
// open file with an int_vector_buffer.
// Default is: open existing file, use 1MB Buffer, 64bit for each integer and int_vector format
int_vector_buffer<> ivb(tmp_file);
if (!ivb.is_open()) {
std::cerr << "ERROR: ivb could not be opend with file " << tmp_file << size << std::endl;
return 1;
}
if (ivb.size() != size) {
std::cerr << "ERROR: ivb.size()="<< ivb.size() << " != " << size << std::endl;
return 1;
}
rng.seed(13); // To get the same values than before use the same seed
for (uint64_t i=0; i<ivb.size(); ++i) {
uint64_t expected_value = rng();
if (ivb[i] != expected_value) {
std::cerr << "ERROR: ivb["<< i << "]=" << ivb[i] << " != " << expected_value << "= expected_value" << std::endl;
return 1;
}
}
ivb.close(true); // close buffer and (3) remove the file
}
return 0;
}
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