C++ .empty()

In C++, the .empty() method checks if a given deque container is empty (i.e., if its size is 0). The method returns true if it is empty and false otherwise.

Syntax

dequeName.empty();

• dequeName: The variable name of the deque being checked for emptiness.

Example

The example below showcases the use of the .empty() method:

#include <iostream>
#include <deque>

int main() {
  // Create a deque of integers
  std::deque<int> numbers;

  // Add elements to the deque
  numbers.push_back(100);
  numbers.push_back(150);

  std::cout << "Deque is empty: ";
  if (numbers.empty()) {
    std::cout << "True";
  }
  else {
    std::cout << "False";
  }

  std::cout << std::endl;

  return 0;
}

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The above code generates the following output:

Deque is empty: False

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Codebyte Example

The following codebyte uses the .clear() method on a deque and checks its emptiness by outputting a boolean value using the .empty() method:

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