69 lines
2.6 KiB
C++
69 lines
2.6 KiB
C++
// fig14_02.cpp
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// Algorithms fill, fill_n, generate and generate_n.
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#include <algorithm> // algorithm definitions
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#include <array> // array class-template definition
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#include <iostream>
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#include <iterator> // ostream_iterator
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// returns the next letter (starts with A)
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char nextLetter() {
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static char letter{'A'};
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return letter++;
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}
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int main() {
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std::array<char, 10> chars{};
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std::ranges::fill(chars, '5'); // fill chars with 5s
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std::cout << "chars after filling with 5s: ";
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std::ostream_iterator<char> output{std::cout, " "};
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std::ranges::copy(chars, output);
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// fill first five elements of chars with 'A's
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std::ranges::fill_n(chars.begin(), 5, 'A');
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std::cout << "\nchars after filling five elements with 'A's: ";
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std::ranges::copy(chars, output);
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// generate values for all elements of chars with nextLetter
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std::ranges::generate(chars, nextLetter);
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std::cout << "\nchars after generating letters A-J: ";
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std::ranges::copy(chars, output);
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// generate values for first five elements of chars with nextLetter
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std::ranges::generate_n(chars.begin(), 5, nextLetter);
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std::cout << "\nchars after generating K-O into elements 0-4: ";
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std::ranges::copy(chars, output);
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// generate values for first three elements of chars with a lambda
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std::ranges::generate_n(chars.begin(), 3,
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[]() { // lambda that takes no arguments
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static char letter{'A'};
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return letter++;
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}
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);
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std::cout << "\nchars after generating A-C into elements 0-2: ";
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std::ranges::copy(chars, output);
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std::cout << "\n";
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}
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/**************************************************************************
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* (C) Copyright 1992-2021 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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