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Foreach in C++ | C++ 11

 C++ 03:

    for (vector::iterator itr = v.begin(); itr!=v.end(); ++ itr)
      cout << (*itr);


C++ 11:
 
for (auto i: v) { // works on any class that has begin() and end()
      cout << i ;    // readonly access
   }

    for (auto& i: v) {
      i++;                 // changes the values in v
   }                       // and also avoids copy construction
Auto Syntax:

    auto x = begin(v);  // Same as: int x = v.begin();

    int arr[4] = {3, 2, 4, 5};
   auto y = begin(arr); // y == 3
   auto z = end(arr);   // z == 5
   

 // How this worked? Because begin() and end() are defined for array.
// Adapt your code to third party library by defining begin() and end() for their containers.
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