how to remove an element from a vector by value c++

To remove an element from a vector in C++ by its value, you can follow these steps:

Step 1: Include the necessary header file for using vectors:

#include <vector>

Step 2: Create a vector and populate it with some initial values:

std::vector<int> myVector = {1, 2, 3, 4, 5};

Step 3: Determine the value of the element you want to remove from the vector. Let's say you want to remove the value 3.

Step 4: Use the std::remove algorithm along with the std::erase function to remove the element.

myVector.erase(std::remove(myVector.begin(), myVector.end(), 3), myVector.end());

The std::remove algorithm moves all the elements that are equal to the specified value to the end of the vector, and returns an iterator pointing to the first element that should be removed. The std::erase function then removes the elements from that iterator to the end of the vector.

Step 5: Check if the element was successfully removed by printing the updated vector:

for (int element : myVector) {
    std::cout << element << " ";
}

This will output: 1 2 4 5, showing that the element with the value 3 has been removed.

And that's it! The element has been removed from the vector.

Note: The std::remove algorithm does not actually remove elements from the vector. It only moves them to the end and returns an iterator. The std::erase function is used to actually remove the elements from the vector.