include <cstdlib>
  include <iostream>
  using namespace std;
  
  void memoryLeak()
  {
      int* ip = new int[1000];
      return; // Bug! Not freeing ip.
  }
  
  void mismatchedFree()
  {
      int* ip1 = (int *)malloc(sizeof(int));
      int* ip2 = new int;
      int* ip3 = new int[1000];
      delete ip1; // BUG! Should use free
      delete [] ip2; // BUG! Should use delete
      free (ip3); // BUG! Should use delete []
  }
  
  void doubleFree()
  {
      int* ip1 = new int[1000];
      delete [] ip1;
      int* ip2 = new int[1000];
      delete [] ip1; // BUG! freeing ip1 twice
  }
  
  void freeUnallocated()
  {
      int* ip1 =
          reinterpret_cast<int*>(10000);    // BUG! ip1 is not a valid pointer.
      delete ip1;
  }
  
  void freeStack()
  {
      int x;
      int* ip = &x;
      delete ip; // BUG! Freeing stack memory
  }
  
  void accessInvalid()
  {
      int* ip1 =
          reinterpret_cast<int*>(10000);    // BUG! ip1 is not a valid pointer
      *ip1 = 5;
  }
  
  void accessFreed()
  {
      int* ip1 = new int;
      delete ip1;
      int* ip2 = new int;
      // BUG! The memory pointed to by ip1
      // has been freed
      *ip1 = 5;
  }
  
  void accessElsewhere()
  {
      int x, y[10], z;
      x = 0;
      z = 0;
      // BUG! element 10 is past the
      // end of the array
      for (int i = 0; i <= 10; i++) {
          y[i] = 10;
       }
  }
  
  void readUninitialized()
  {
      int* ip;
      cout << *ip << endl; // BUG! ip is uninitialized
  }
  
  int main(int argc, char** argv)
  {
    cout << "Memory leak\n";
    memoryLeak();
    cout << "Mismatched Free\n";
    mismatchedFree();
    cout << "Double Free\n";
    doubleFree();
    cout << "Free Unallocated\n";
    freeUnallocated();
    cout << "Free Stack\n";
    freeStack();
    cout << "Access Invalid\n";
    accessInvalid();
    cout << "Access Freed\n";
    accessFreed();
    cout << "Access Elsewhere\n";
    accessElsewhere();
    cout << "Read Uninitialized\n";
    readUninitialized();
  }