Modern c++11

reverse.cpp

#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <future>

using namespace std;

string flip(string s) {
    reverse( begin(s), end(s) );
    return s;
}

int main() {
    vector<future<string>> v;

    v.push_back( async([]{ return flip(" ,olleH"); }));
    v.push_back( async([]{ return flip(".gnaL");   }));
    v.push_back( async([]{ return flip("\n!TXEN"); }));

    for (auto& e: v) {
        cout << e.get();
    }
}

After installing gcc 4.7 with macports, I was able to compile this on my Mac with:

g++-mp-4.7 -std=c++11 -o main main.cpp