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/*
* Transforms a sequence of 64-bit integers into a bit-compressed integer vector.
* The first command line parameter argv[1] specifies the file, which contains the sequence
* of integers.
* The bit-compressed integer vector is stored in a file called `argv[1].int_vector`.
*/
#include <sdsl/util.hpp>
#include <sdsl/int_vector.hpp>
#include <iostream>
#include <string>
using namespace sdsl;
using namespace std;
int main(int argc, char* argv[])
{
if (argc < 2) {
cout << "Usage: " << argv[0] << " int_file" << endl;
return 1;
}
size_t x = util::file_size(argv[1]);
const int BPI=8;
cout<<"file size in bytes = "<<x<<endl;
if (x % BPI != 0) {
cout << "Error: x%"<<BPI<<" != 0"<<endl;
return 1;
}
// (1) scan file and determine the largest value
int_vector_buffer<64> ivb(string(argv[1]), std::ios::in, 6400000, 64, true);
if (!ivb.is_open()) {
cout<<"ERROR: could not open file "<<argv[1]<<endl;
return 1;
}
uint64_t max=0;
for (size_t i=0; i<ivb.size(); ++i) {
if (ivb[i] > max)
max = ivb[i];
}
cout<<"Max value: "<<max<<endl;
uint8_t width = bits::hi(max)+1;
cout<<"width="<<(int)width<<endl;
// (2) scan file, bit-compress values and write to outfile
string ofile = string(argv[1])+".int_vector";
int_vector_buffer<> ivb2(ofile, std::ios::out, 6400000, width);
if (!ivb2.is_open()) {
cout<<"ERROR: could not open output file "<<argv[1]<<endl;
return 1;
}
for (size_t i=0; i<ivb.size(); ++i) {
ivb2[i] = ivb[i];
}
ivb.close();
ivb2.close();
int_vector<> v;
load_from_file(v, ofile);
cout<<"v.size()="<<v.size()<<endl;
cout<<"v[0]="<<v[0]<<endl;
const bool do_check = false;
if (do_check) {
int_vector<> check;
load_vector_from_file(check, argv[1], BPI);
if (check.size() != v.size()) {
cout<<"Vectors differ in size: "<<check.size()<<"!="<<v.size()<<endl;
return 1;
}
for (size_t i=0; i<check.size(); ++i) {
if (check[i] != v[i]) {
cout<<"vectors differ in position "<<i<<": "<<check[i]<<"!="<<v[i]<<endl;
}
}
}
}
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