23 lines
388 B
C++
23 lines
388 B
C++
#include <iostream>
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#include <functional>
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template<class Func>
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typename Func::result_type first(Func func, typename Func::argument_type arg)
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{
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return func(arg);
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}
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class second : public std::unary_function<int, int>
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{
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public:
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result_type operator()(argument_type arg) const
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{
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return arg * arg;
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}
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};
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int main()
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{
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std::cout << first(second(), 2) << std::endl;
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return 0;
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}
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