C++/Vector/vector insert

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Appending values to Vector Containers after sorting

  
#include <algorithm>
#include <vector>
#include <iostream>
using namespace std;
template <class T>
void print(T& c){
   for( typename T::iterator i = c.begin(); i != c.end(); i++ ){
      std::cout << *i << endl;
   }
}
int main( ){
   const char* names1[] = { "A", "B", "C" };
   const char* names2[] = { "D", "E", "F", "G" };
   vector<string> squad1( names1,names1 + sizeof( names1 ) / sizeof( names1[0] ) );
   vector<string> squad2( names2,names2 + sizeof( names2 ) / sizeof( names2[0] ) ); 
   sort( squad1.begin(), squad1.end() );
   
   print( squad1);
   sort( squad2.begin(), squad2.end() );
   print( squad2);
   squad1.insert( squad1.end(), squad2.begin(), squad2.end() );
   print( squad1); 
   sort( squad1.begin(), squad1.end() );
   print( squad1);
}


Combine insert and end to add elements to the end of vector

   
#include <iostream>
#include <cassert>
#include <algorithm>
#include <string>
#include <list>
#include <deque>
#include <vector>
using namespace std;
int main()
{
  vector<string> vec;

  vec.insert(vec.end(), "AAA");
  vec.insert(vec.end(), "BBBB");
  vec.insert(vec.end(), "CCCCC");

  vector<string>::iterator pos;

  for (pos=vec.begin(); pos!=vec.end(); ++pos) {
        cout << *pos << " ";
  }
  return 0;
}
/* 
AAA BBBB CCCCC 
 */


Create and initialize vector with float number array

  
#include <algorithm>
#include <cmath>
#include <functional>
#include <iostream>
#include <list>
#include <numeric>
#include <vector>
using namespace std;
template <class T>
void print(T& c){
   for( typename T::iterator i = c.begin(); i != c.end(); i++ ){
      std::cout << *i << endl;
   }
}
int main( ){
   const float a[] = { 1, 1.3, 1.5, 0.9, 0.1, 0.2};
   vector<float> data( a,a + sizeof( a ) / sizeof( a[0] ) );
   cout << data.size() << " ELEMENTS\n";
   print( data  );
}


Insert 10 duplicate value to vector

   
#include <iostream>
#include <vector>
using namespace std;
int main()
{
  vector<char> v(10);
  vector<char> v2;
  char str[] = "<Vector>";
  unsigned int i;
  for(i=0; i<10; i++) 
     v[i] = i + "a";
  for(i=0; str[i]; i++) 
     v2.push_back(str[i]);
  
  cout << "Original contents of v:\n";
  for(i=0; i<v.size(); i++) 
      cout << v[i] << " ";
  cout << "\n\n";
  vector<char>::iterator p = v.begin();
  p += 2; // point to 3rd element
  v.insert(p, 10, "X");
  // display contents after insertion
  cout << "Size after inserting X"s = " << v.size() << endl;
  cout << "Contents after insert:\n";
  for(i=0; i<v.size(); i++) cout << v[i] << " ";
  cout << "\n\n";
  return 0;
}
/* 
Original contents of v:
a b c d e f g h i j
Size after inserting X"s = 20
Contents after insert:
a b X X X X X X X X X X c d e f g h i j

 */


Insert characters into vector. An iterator to the inserted object is returned

   
#include <iostream>
#include <vector>
using namespace std;
void show(const char *msg, vector<char> vect);
int main() {
  vector<char> v;
  vector<char>::iterator itr;
  itr = v.begin();
  itr = v.insert(itr, "A");
  itr = v.insert(itr, "B");
  v.insert(itr, "C");
  return 0;
}
void show(const char *msg, vector<char> vect) {
  vector<char>::iterator itr;
  cout << msg << endl;
  for(itr=vect.begin(); itr != vect.end(); ++itr)
    cout << *itr << endl;
}


Insert element at specific position

   
#include <vector>
#include <algorithm>
#include <iterator>
#include <iostream>
using namespace std;
void printVector(const vector<int>& v){
  copy(v.begin(), v.end(), ostream_iterator<int>(cout, " "));
  cout << endl;
}
int main(int argc, char** argv){
  vector<int> v1, v2;
  int i;
  v1.push_back(1);
  v1.push_back(2);
  v1.push_back(3);
  v1.push_back(5);
  // Insert it in the correct place
  v1.insert(v1.begin() + 3, 4);
  printVector(v1);
  return (0);
}


Insert element by index

   
 
#include <iostream>
using std::cout;
using std::endl;
#include <vector>    // vector class-template definition
#include <algorithm> // copy algorithm
#include <iterator>  // ostream_iterator iterator
#include <stdexcept> // out_of_range exception
int main()
{
   int array[ 6 ] = { 1, 2, 3, 4, 5, 6 };
   std::vector< int > integers( array, array + 6 );
   std::ostream_iterator< int > output( cout, " " );
   integers.push_back( 2 );
   integers.push_back( 3 );
   integers.push_back( 4 );
   cout << "Vector integers contains: ";
   std::copy( integers.begin(), integers.end(), output );
   // insert 22 as 2nd element
   integers.insert( integers.begin() + 1, 22 );
   cout << "\n\nVector integers contains: ";
   std::copy( integers.begin(), integers.end(), output );
   return 0;
}
/* 
Vector integers contains: 1 2 3 4 5 6 2 3 4
Vector integers contains: 1 22 2 3 4 5 6 2 3 4 
 */


Insert elements from array

   
 
#include <iostream>
using std::cout;
using std::endl;
#include <vector>    // vector class-template definition
#include <algorithm> // copy algorithm
#include <iterator>  // ostream_iterator iterator
#include <stdexcept> // out_of_range exception
int main()
{
   int array[ 6 ] = { 1, 2, 3, 4, 5, 6 };
   std::vector< int > integers( array, array + 6 );
   std::ostream_iterator< int > output( cout, " " );
   integers.push_back( 2 );
   integers.push_back( 3 );
   integers.push_back( 4 );
   cout << "Vector integers contains: ";
   std::copy( integers.begin(), integers.end(), output );
   // insert elements from array
   integers.insert( integers.begin(), array, array + 6 );
   cout << "\n\nContents of vector integers before clear: ";
   std::copy( integers.begin(), integers.end(), output );

   return 0;
}
/* 
Vector integers contains: 1 2 3 4 5 6 2 3 4
Contents of vector integers before clear: 1 2 3 4 5 6 1 2 3 4 5 6 2 3 4 
 */


Insert one vector to another vector

   
 

#include <iostream>
#include <vector>
using namespace std;
int main()
{
  vector<char> v(10);
  vector<char> v2;
  char str[] = "<Vector>";
  unsigned int i;
  for(i=0; i<10; i++)
     v[i] = i + "a";
  for(i=0; str[i]; i++)
     v2.push_back(str[i]);
  cout << "Original contents of v:\n";
  for(i=0; i<v.size(); i++)
      cout << v[i] << " ";
  cout << "\n\n";
  vector<char>::iterator p = v.begin();
  p += 2; // point to 3rd element
  v.insert(p, 10, "X");
  // display contents after insertion
  cout << "Size after inserting X"s = " << v.size() << endl;
  cout << "Contents after insert:\n";
  for(i=0; i<v.size(); i++) cout << v[i] << " ";
  cout << "\n\n";

  // Insert v2 into v
  v.insert(p, v2.begin(), v2.end());
  cout << "Size after v2"s insertion = ";
  cout << v.size() << endl;
  cout << "Contents after insert:\n";
  for(i=0; i<v.size(); i++) cout << v[i] << " ";
  cout << endl;
  return 0;
}
/* 
Original contents of v:
a b c d e f g h i j
Size after inserting X"s = 20
Contents after insert:
a b X X X X X X X X X X c d e f g h i j

 */


Inserts an element into a vector at given position

  
#include <iostream>
#include <string>
#include <vector>
using namespace std;
void insert(vector<string>& v, int pos, string s)
{  
   int last = v.size() - 1; 
   v.push_back(v[last]);
   for (int i = last; i > pos; i--)
      v[i] = v[i - 1];
   v[pos] = s;
}
void print(vector<string> v)
{  
   for (int i = 0; i < v.size(); i++)
      cout << "[" << i << "] " << v[i] << "\n";
}
int main()
{  
   vector<string> staff(5);
   staff[0] = "A";
   staff[1] = "B";
   staff[2] = "C";
   staff[3] = "D";
   staff[4] = "E";
   print(staff);
   int pos;
   cout << "Insert before which element? ";
   cin >> pos;
   insert(staff, pos, "New, Nina");
   print(staff);
   return 0;
}