46 lines
1.4 KiB
C++
46 lines
1.4 KiB
C++
#include <iostream>
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#include <limits>
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#include <boost/rational.hpp>
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#include <boost/safe_numerics/safe_integer.hpp>
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int main(int, const char *[]){
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// simple demo of rational library
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const boost::rational<int> r {1, 2};
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std::cout << "r = " << r << std::endl;
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const boost::rational<int> q {-2, 4};
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std::cout << "q = " << q << std::endl;
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// display the product
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std::cout << "r * q = " << r * q << std::endl;
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// problem: rational doesn't handle integer overflow well
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const boost::rational<int> c {1, INT_MAX};
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std::cout << "c = " << c << std::endl;
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const boost::rational<int> d {1, 2};
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std::cout << "d = " << d << std::endl;
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// display the product - wrong answer
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std::cout << "c * d = " << c * d << std::endl;
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// solution: use safe integer in rational definition
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using safe_rational = boost::rational<
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boost::safe_numerics::safe<int>
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>;
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// use rationals created with safe_t
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const safe_rational sc {1, INT_MAX};
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std::cout << "c = " << sc << std::endl;
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const safe_rational sd {1, 2};
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std::cout << "d = " << sd << std::endl;
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std::cout << "c * d = ";
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try {
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// multiply them. This will overflow
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std::cout << sc * sd << std::endl;
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}
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catch (std::exception const& e) {
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// catch exception due to multiplication overflow
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std::cout << e.what() << std::endl;
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}
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return 0;
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}
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