cpp/algorithm/sort

1. include <algorithm>
2. include <functional>
3. include <array>
4. include <iostream>

int main() {

   std::array<int, 10> s = {5, 7, 4, 2, 8, 6, 1, 9, 0, 3}; 

   // sort using the default operator<
   std::sort(s.begin(), s.end());
   for (int a : s) {
       std::cout << a << " ";
   }   
   std::cout << '\n';

   // sort using a standard library compare function object
   std::sort(s.begin(), s.end(), std::greater<int>());
   for (int a : s) {
       std::cout << a << " ";
   }   
   std::cout << '\n';

   // sort using a custom function object
   struct {
       bool operator()(int a, int b)
       {   
           return a < b;
       }   
   } customLess;
   std::sort(s.begin(), s.end(), customLess);
   for (int a : s) {
       std::cout << a << " ";
   }   
   std::cout << '\n';

   // sort using a lambda expression 
   std::sort(s.begin(), s.end(), [](int a, int b) {
       return b < a;   
   });
   for (int a : s) {
       std::cout << a << " ";
   } 
   std::cout << '\n';

}