/***************************************************************************
*  algo/test_scan.cpp
*
*  Part of the STXXL. See http://stxxl.sourceforge.net
*
*  Copyright (C) 2002 Roman Dementiev <dementiev@mpi-sb.mpg.de>
*
*  (See accompanying file LICENSE_1_0.txt or copy at
**************************************************************************/

//! \example algo/test_scan.cpp
//! This is an example of how to use \c stxxl::for_each() and \c stxxl::find() algorithms

#include <iostream>
#include <algorithm>

#include <stxxl/vector>
#include <stxxl/scan>

using stxxl::int64;
using stxxl::timestamp;

template <typename type>
struct counter
{
type value;
counter(type v = type(0)) : value(v) { }
type operator () ()
{
type old_val = value;
value++;
return old_val;
}
};

template <typename type>
struct square
{
void operator () (type & arg)
{
arg = arg * arg;
}
};

template <typename type>
struct fill_value
{
type val;
fill_value(const type & v_) : val(v_) { }

type operator () ()
{
return val;
}
};

int main()
{
stxxl::vector<int64>::size_type i;
stxxl::vector<int64> v(64 * int64(1024 * 1024));
double b, e;

STXXL_MSG("write " << (v.end() - v.begin()) << " elements ...");

stxxl::generate(v.begin(), v.end(), counter<int64>(), 4);

STXXL_MSG("for_each_m ...");
b = timestamp();
stxxl::for_each_m(v.begin(), v.end(), square<int64>(), 4);
e = timestamp();
STXXL_MSG("for_each_m time: " << (e - b));

STXXL_MSG("check");
for (i = 0; i < v.size(); ++i)
{
if (v[i] != int64(i * i))
STXXL_MSG("Error at position " << i);
}

STXXL_MSG("Pos of value    1023: " << (stxxl::find(v.begin(), v.end(), 1023, 4) - v.begin()));
STXXL_MSG("Pos of value 1048576: " << (stxxl::find(v.begin(), v.end(), 1024 * 1024, 4) - v.begin()));
STXXL_MSG("Pos of value    1024: " << (stxxl::find(v.begin(), v.end(), 32 * 32, 4) - v.begin()));

STXXL_MSG("generate ...");
b = timestamp();

stxxl::generate(v.begin() + 1, v.end() - 1, fill_value<int64>(555), 4);
e = timestamp();
STXXL_MSG("generate: " << (e - b));

STXXL_MSG("check");
if (v[0] != 0)
STXXL_MSG("Error at position " << i);
if (v[v.size() - 1] != int64((v.size() - 1) * (v.size() - 1)))
STXXL_MSG("Error at position " << i);

for (i = 1; i < v.size() - 1; ++i)
{
if (v[i] != 555)
STXXL_MSG("Error at position " << i);
}

return 0;
}