Answers for "how to empty vector c++"

delete from front in vector c++

// Deleting first element
vector_name.erase(vector_name.begin());

// Deleting xth element from start
vector_name.erase(vector_name.begin()+(x-1));

// Deleting from the last
vector_name.pop_back();

vector c++ empty it

// clearing vectors
#include <iostream>
#include <vector>

int main ()
{
  std::vector<int> myvector;
  myvector.push_back (100);
  myvector.push_back (200);
  myvector.push_back (300);

  std::cout << "myvector contains:";
  for (unsigned i=0; i<myvector.size(); i++)
    std::cout << ' ' << myvector[i];
  std::cout << 'n';

  myvector.clear(); // making myverctor.empty() == 1
  myvector.push_back (1101);
  myvector.push_back (2202);

  std::cout << "myvector contains:";
  for (unsigned i=0; i<myvector.size(); i++)
    std::cout << ' ' << myvector[i];
  std::cout << 'n';

  return 0;
}

Empty the vector

//C++ STL program to demonstrate example of
//vector::empty() function

#include <iostream>
#include <vector>
using namespace std;

int main()
{
    vector<int> v1;

    //printing the size of the vector
    cout << "Total number of elements: " << v1.size() << endl;
    //checking whether vector is empty or not
    if (v1.empty())
        cout << "vector is empty." << endl;
    else
        cout << "vector is not empty." << endl;

    //pushing elements
    v1.push_back(10);
    v1.push_back(20);
    v1.push_back(30);
    v1.push_back(40);
    v1.push_back(50);

    //printing the size of the vector
    cout << "Total number of elements: " << v1.size() << endl;
    //checking whether vector is empty or not
    if (v1.empty())
        cout << "vector is empty." << endl;
    else
        cout << "vector is not empty." << endl;

    return 0;
}