C++ Tutorial/STL Algorithms Helper/bind2nd

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Demonstrate bind2nd()

#include <iostream>
#include <list>
#include <functional>
#include <algorithm>
using namespace std;
int main()
{
  list<int> lst;
  list<int>::iterator p, endp;
  for(int i=1; i < 20; i++) lst.push_back(i);
  cout << "Original sequence:\n";
  p = lst.begin();
  while(p != lst.end()) {
    cout << *p << " ";
    p++;
  }
  cout << endl;
  endp = remove_if(lst.begin(), lst.end(),
                   bind2nd(greater<int>(), 8));
  cout << "Resulting sequence:\n";
  p = lst.begin();
  while(p != endp) {
    cout << *p << " ";
    p++;
  }
  return 0;
}
Original sequence:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
Resulting sequence:
1 2 3 4 5 6 7 8

replace_if bind2nd and greater

#include <algorithm>
#include <functional>
#include <vector>
#include <iostream>
using namespace std;
void print(int elem)
{
  cout << elem << " ";
}
int main(int argc, char** argv)
{
  vector<int> myVector;
  myVector.push_back(1);
  myVector.push_back(2);
  myVector.push_back(3);
  myVector.push_back(4);
  myVector.push_back(5);
  myVector.push_back(6);

  replace_if(myVector.begin(), myVector.end(), bind2nd(greater<int>(), 100),100);
  for_each(myVector.begin(), myVector.end(), &print);
  cout << endl;
  return (0);
}

replace_if, bind2nd and less

#include <algorithm>
#include <functional>
#include <vector>
#include <iostream>
using namespace std;
void print(int elem)
{
  cout << elem << " ";
}
int main(int argc, char** argv)
{
  vector<int> myVector;
  myVector.push_back(1);
  myVector.push_back(2);
  myVector.push_back(3);
  myVector.push_back(4);
  myVector.push_back(5);
  myVector.push_back(6);

  replace_if(myVector.begin(), myVector.end(), bind2nd(less<int>(), 0), 0);
  replace_if(myVector.begin(), myVector.end(), bind2nd(greater<int>(), 100),100);
  for_each(myVector.begin(), myVector.end(), &print);
  cout << endl;
  return (0);
}

trasform, bind2nd and plus

#include <algorithm>
#include <functional>
#include <iostream>
#include <vector>
using namespace std;
void print(int elem)
{
  cout << elem << " ";
}
int main(int argc, char** argv)
{
  vector<int> myVector;
  myVector.push_back(1);
  myVector.push_back(2);
  myVector.push_back(3);
  myVector.push_back(4);

  for_each(myVector.begin(), myVector.end(), &print);
  transform(myVector.begin(), myVector.end(), myVector.begin(),bind2nd(plus<int>(), 100));
  for_each(myVector.begin(), myVector.end(), &print);
  cout << endl;
  return (0);
}

Use bind2nd() to create a unary function object that will return true when a value is greater than 10.

#include <iostream>
#include <list>
#include <functional>
#include <algorithm>
using namespace std;
int main()
{
  list<int> list1;
  list<int>::iterator res_itr;
  for(unsigned i=1; i < 20; ++i) list1.push_back(i);
  res_itr = remove_if(list1.begin(), list1.end(),bind2nd(greater<int>(), 10));
  return 0;
}

Use the generic count algorithm with predicate: Determine the number of array elements that are not equal to 1

#include <iostream>
#include <cassert>
#include <algorithm>
#include <functional>
using namespace std;
int main()
{
  int a[] = {0, 0, 0, 1, 1, 1, 2, 2, 2};
  int final_count = count_if(&a[0], &a[9], bind2nd(not_equal_to<int>(), 1));
  cout << final_count << endl;  
  return 0;
}
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