37 lines
862 B
C++
37 lines
862 B
C++
// Copyright (C) 2001-2003
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// William E. Kempf
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//
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// Distributed under the Boost Software License, Version 1.0. (See accompanying
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// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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#include <boost/thread/thread.hpp>
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#include <iostream>
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const int NUM_CALCS=5;
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class factorial
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{
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public:
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factorial(int x, int& res) : x(x), res(res) { }
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void operator()() { res = calculate(x); }
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int result() const { return res; }
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private:
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int calculate(int x) { return x <= 1 ? 1 : x * calculate(x-1); }
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private:
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int x;
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int& res;
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};
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int main()
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{
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int results[NUM_CALCS];
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boost::thread_group thrds;
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for (int i=0; i < NUM_CALCS; ++i)
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thrds.create_thread(factorial(i*10, results[i]));
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thrds.join_all();
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for (int j=0; j < NUM_CALCS; ++j)
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std::cout << j*10 << "! = " << results[j] << std::endl;
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}
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