C++ <list> remove function
removeis used in list toremove all elements equal to the specified valueis a function that is a highly efficient operation unique to linked lists.
removeis a member function of the container class, used to delete all elements in the linked list that equal the specified value.
In the list,removethe time complexity is O(n).
Word Definitions： removemeans "remove", i.e., delete all elements equal to the specified value.
Basic syntax and parameters
Syntax format
void remove(const T& value);
Parameter description
- Parameter：
value- the value of the element to delete
Function description
- Return Value：
void(No return value). - Effect: Delete all elements in the linked list that equal value.
Example
Example 1: Delete all elements equal to the specified value
Example
#include <iostream>
#include <list>
int main() {
std::list<int> numbers = {1, 2, 3, 2, 4, 2, 5};
std::cout << "Original: ";
for(int n : numbers) std::cout << n << " ";
std::cout << std::endl;
// Delete all elements equal to 2
numbers.remove(2);
std::cout << "After remove(2): ";
for(int n : numbers) std::cout << n << " ";
std::cout << std::endl;
return 0;
}
#include <list>
int main() {
std::list<int> numbers = {1, 2, 3, 2, 4, 2, 5};
std::cout << "Original: ";
for(int n : numbers) std::cout << n << " ";
std::cout << std::endl;
// Delete all elements equal to 2
numbers.remove(2);
std::cout << "After remove(2): ";
for(int n : numbers) std::cout << n << " ";
std::cout << std::endl;
return 0;
}
Expected running result:
原始: 1 2 3 2 4 2 5 remove(2) 后: 1 3 4 5
Example 2: Delete a string
Example
#include <iostream>
#include <list>
#include <string>
int main() {
std::list<std::string> words = {"apple", "banana", "apple", "cherry", "apple"};
std::cout << "Original: ";
for(const auto& w : words) std::cout << w << " ";
std::cout << std::endl;
words.remove("apple");
std::cout << "remove(\"apple\") After: ";
for(const auto& w : words) std::cout << w << " ";
std::cout << std::endl;
return 0;
}
#include <list>
#include <string>
int main() {
std::list<std::string> words = {"apple", "banana", "apple", "cherry", "apple"};
std::cout << "Original: ";
for(const auto& w : words) std::cout << w << " ";
std::cout << std::endl;
words.remove("apple");
std::cout << "remove(\"apple\") After: ";
for(const auto& w : words) std::cout << w << " ";
std::cout << std::endl;
return 0;
}
Expected running result:
原始: apple banana apple cherry apple
remove("apple") 后: banana cherry
other extensions