#include <iostream>
#include <vector>
 
int
main(void) {
 
    std::vector<double> a = {0.5, -0.5, 1.5, 2.0};
    std::vector<double> b = {3.5, 5.5, 3.0, -1.0};
    std::vector<double> c(5);
    auto i = 0;
 
    for(auto it1 = a.begin(), it2 = b.begin();
        it1 != a.end();
        ++it1, ++it2
    )
    {
        c[i] = ((*it1 + *it2) + 1) / 2;
        std::cout << c[i] << ' ';
        ++i;
    }
    return 0;
}

auto expr = ...;
auto x1 = process_function1(expr);
auto x2 = process_function2(x1);
auto x3 = process_function3(x2);
...
auto xN = process_functionN(xN-1);

#include <iostream>
#include <vector>
 
int main(void) 
{
    const int n = 4;
    double a[]  = {0.5, -0.5, 1.5, 2.0};
    double b[] =  {3.5, 5.5, 3.0, -1.0};
    double c[n];
    for(int i=0;i<n;i++)
    {
        c[i] = (*(a+i)+*(b+i) + 1)/2;
        std::cout << c[i] << ' ';
    }
    std::cout<<std::endl;
    return 0;
}

import std.stdio;
 
void main()
{
    auto twice = function (int x) => x * 2;
 
    auto square = delegate (int x) => x * x;
 
    foreach (i; 0 .. 10)
        writeln(twice(i), '\t', square(i));
}