51 lines
2.1 KiB
C++
51 lines
2.1 KiB
C++
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// fig06_03.cpp
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// Using range-based for.
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#include <format>
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#include <iostream>
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#include <array>
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int main() {
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std::array items{1, 2, 3, 4, 5}; // type inferred as array<int, 5>
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// display items before modification
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std::cout << "items before modification: ";
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for (const int& item : items) { // item is a reference to a const int
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std::cout << std::format("{} ", item);
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}
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// multiply the elements of items by 2
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for (int& item : items) { // item is a reference to an int
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item *= 2;
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}
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// display items after modification
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std::cout << "\nitems after modification: ";
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for (const int& item : items) {
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std::cout << std::format("{} ", item);
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}
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// sum elements of items using range-based for with initialization
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std::cout << "\n\ncalculating a running total of items' values:\n";
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for (int runningTotal{0}; const int& item : items) {
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runningTotal += item;
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std::cout << std::format("item: {}; running total: {}\n",
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item, runningTotal);
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}
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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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