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/***************************************************************************
* utils/log2.cpp
*
* Part of the STXXL. See http://stxxl.sourceforge.net
*
* Copyright © 2008 Andreas Beckmann <beckmann@cs.uni-frankfurt.de>
*
* Distributed under the Boost Software License, Version 1.0.
* (See accompanying file LICENSE_1_0.txt or copy at
* http://www.boost.org/LICENSE_1_0.txt)
**************************************************************************/
#include <iostream>
#include <stxxl.h>
using stxxl::LOG2;
using stxxl::unsigned_type;
template <unsigned_type i>
void log_i()
{
std::cout << i << "\t" << (i < 1000000 ? "\t" : "")
<< stxxl::LOG2_floor<i>::value << "\t"
<< stxxl::LOG2<i>::floor << "\t"
<< stxxl::LOG2<i>::ceil << std::endl;
}
template <unsigned_type i>
void log_ipm1()
{
log_i<i - 1>();
log_i<i>();
log_i<i + 1>();
std::cout << std::endl;
}
int main()
{
std::cout << "i\t\tLOG2<i>\tLOG2<i>\tLOG2<i>" << std::endl;
std::cout << "\t\t\tfloor\tceil" << std::endl;
log_ipm1<1 << 0>();
log_ipm1<1 << 1>();
log_ipm1<1 << 2>();
log_ipm1<1 << 3>();
log_ipm1<1 << 4>();
log_ipm1<1 << 5>();
log_ipm1<1 << 6>();
log_ipm1<1 << 7>();
log_ipm1<1 << 8>();
log_ipm1<1 << 9>();
log_ipm1<1 << 10>();
log_ipm1<1 << 11>();
log_ipm1<1 << 12>();
log_ipm1<1 << 16>();
log_ipm1<1 << 24>();
log_ipm1<1 << 30>();
log_ipm1<1UL << 31>();
#if __WORDSIZE == 64
log_ipm1<1UL << 32>();
log_ipm1<1UL << 33>();
log_ipm1<1UL << 48>();
log_ipm1<1UL << 63>();
#endif
}
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