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#include "../mng/mng.h"
#include "sort.h"
#include "../containers/vector"
//! \example algo/sort.cpp
//! This is an example of how to use \c stxxl::sort() algorithm
using namespace stxxl;
struct my_type
{
typedef unsigned key_type;
key_type _key;
char _data[128 - sizeof(key_type)];
key_type key() const {return _key; };
my_type() {};
my_type(key_type __key):_key(__key) {};
static my_type min_value(){ return my_type(0); };
static my_type max_value(){ return my_type(0xffffffff); };
};
bool operator < (const my_type & a, const my_type & b)
{
return a.key() < b.key();
}
struct cmp: public std::less<my_type>
{
my_type min_value() const { return my_type(0); };
my_type max_value() const { return my_type(0xffffffff); };
};
int main()
{
unsigned memory_to_use = 64*1024*1024;
typedef stxxl::vector<my_type> vector_type;
const stxxl::int64 n_records = 32*1024*1024/sizeof(my_type) - 234;
vector_type v(n_records);
random_number32 rnd;
STXXL_MSG("Filling vector...")
for(stxxl::int64 i=0; i < v.size(); i++)
v[i]._key = rnd();
STXXL_MSG("Checking order...")
STXXL_MSG( ((stxxl::is_sorted(v.begin(),v.end()))?"OK":"WRONG" ));
STXXL_MSG("Sorting...")
stxxl::sort(v.begin(),v.end(),cmp(),memory_to_use);
STXXL_MSG("Checking order...")
STXXL_MSG( ((stxxl::is_sorted(v.begin(),v.end()))?"OK":"WRONG" ));
return 0;
}