cpp-coding-exercise/parallel-transform/main.cpp at main · DoctorLai/cpp-coding-exercise · GitHub

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/**

This shows using parallel transform_reduce from C++17

to perform a fold (reduce) operation on a range of values. e.g. sum up 100 values in parallel

#include <vector>

#include <numeric> // std::transform_reduce

#include <functional> // std::plus

#include <iostream>

#include <execution> // std::execution::par

int

main()

{

std::vector<int> numbers(100);

// Initialize the vector with values 1 to 100

std::iota(numbers.begin(), numbers.end(), 1);

// Use parallel transform_reduce to sum the values in parallel

int sum = std::transform_reduce(

std::execution::par, // parallel execution policy parallel or std::execution::seq for sequential

numbers.begin(),

numbers.end(),

0, // initial value

std::plus<int>{}, // binary operation to combine results

[](int v) { return v; } // unary operation to transform each element

);

std::cout << "Sum of numbers from 1 to 100: " << sum << '\n';

return 0;

}

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