How do I remove_if/erase idiom in C++?

The remove_if/erase idiom is a common C++ technique used to remove elements from a container based on a specific condition. This method combines the `std::remove_if` algorithm with the `erase` method of the container to effectively remove unwanted elements.

Here’s how it works: you first use `std::remove_if` to move the elements that you want to keep to the front of the container, and then you call `erase` to remove the unwanted elements from the end of the container.

Below is an example that demonstrates this idiom by removing all even numbers from a vector:

#include <iostream> #include <vector> #include <algorithm> int main() { std::vector<int> nums = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10}; nums.erase(std::remove_if(nums.begin(), nums.end(), [](int n) { return n % 2 == 0; }), nums.end()); std::cout << "Odd numbers: "; for (const auto &num : nums) { std::cout << num << " "; } return 0; }

C++ remove_if erase idiom vector STL algorithms

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