53 lines
2.1 KiB
C++
53 lines
2.1 KiB
C++
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// fig20_14.cpp
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// Summing the elements of a braced initializer
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#include <fmt/format.h>
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#include <initializer_list>
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#include <iostream>
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#include <string>
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// sum the elements of an initializer_list
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template <typename T>
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T sum(std::initializer_list<T> list) {
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T total{}; // value initialize total based on type T
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// sum all the elements in list; requires += operator for type T
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for (auto item : list) {
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total += item;
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}
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return total;
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}
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int main() {
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// display the sum of four ints contained in a braced initializer
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std::cout << fmt::format("The sum of {} is: {}\n",
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"{1, 2, 3, 4}", sum({1, 2, 3, 4}));
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// display the sum of three doubles contained in a braced initializer
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std::cout << fmt::format("The sum of {} is: {}\n",
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"{1.1, 2.2, 3.3}", sum({1.1, 2.2, 3.3}));
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// display the sum of two strings contained in a braced initializer
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std::string s1{"Happy "};
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std::string s2{"birthday!"};
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std::cout << fmt::format("The sum of {} is: {}\n",
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"{\"Happy \", \"birthday!\"}", sum({s1, s2}));
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}
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/**************************************************************************
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* (C) Copyright 1992-2022 by Deitel & Associates, Inc. and *
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* Pearson Education, Inc. All Rights Reserved. *
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* *
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* DISCLAIMER: The authors and publisher of this book have used their *
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* best efforts in preparing the book. These efforts include the *
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* development, research, and testing of the theories and programs *
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* to determine their effectiveness. The authors and publisher make *
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* no warranty of any kind, expressed or implied, with regard to these *
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* programs or to the documentation contained in these books. The authors *
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* and publisher shall not be liable in any event for incidental or *
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* consequential damages in connection with, or arising out of, the *
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* furnishing, performance, or use of these programs. *
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**************************************************************************/
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