C++ <list> erase Function
eraseis used in list fordeleting elements at specified positionsof the function.
eraseIt is a member function of the container class, used to delete one or more elements at a specified position in the linked list.
In the list,eraseIts time complexity is O(1), because it only requires adjusting pointers.
Word Definitions： eraseIt means "erase," i.e., deleting the element at the specified position.
Basic Syntax and Parameters
eraseis a member function of the container class.
Syntax format
iterator erase(iterator pos); iterator erase(iterator first, iterator last);
Parameter description
- Parameter：
pos- position of the element to be deleted - Parameter：
first, last- range of the elements to be deleted
Function description
- Return Value: Returns an iterator pointing to the next element.
- Effect: deletes the element at the specified position.
Example
Example 1: Deleting a single element
Example
#include <iostream>
#include <list>
int main() {
std::list<int> numbers = {1, 2, 3, 4, 5};
std::cout << "Original: ";
for(int n : numbers) std::cout << n << " ";
std::cout << std::endl;
// Remove the second element
auto it = std::next(numbers.begin(), 1);
numbers.erase(it);
std::cout << "After deletion: ";
for(int n : numbers) std::cout << n << " ";
std::cout << std::endl;
return 0;
}
#include <list>
int main() {
std::list<int> numbers = {1, 2, 3, 4, 5};
std::cout << "Original: ";
for(int n : numbers) std::cout << n << " ";
std::cout << std::endl;
// Remove the second element
auto it = std::next(numbers.begin(), 1);
numbers.erase(it);
std::cout << "After deletion: ";
for(int n : numbers) std::cout << n << " ";
std::cout << std::endl;
return 0;
}
Expected Running Result:
原始: 1 2 3 4 5 After deletion: 1 3 4 5
Example 2: Deleting multiple elements
Example
#include <iostream>
#include <list>
int main() {
std::list<int> numbers = {1, 2, 3, 4, 5, 6, 7};
std::cout << "Original: ";
for(int n : numbers) std::cout << n << " ";
std::cout << std::endl;
// Erase the 2nd to 4th elements
auto first = std::next(numbers.begin(), 1);
auto last = std::next(numbers.begin(), 4);
numbers.erase(first, last);
std::cout << "After deletion: ";
for(int n : numbers) std::cout << n << " ";
std::cout << std::endl;
return 0;
}
#include <list>
int main() {
std::list<int> numbers = {1, 2, 3, 4, 5, 6, 7};
std::cout << "Original: ";
for(int n : numbers) std::cout << n << " ";
std::cout << std::endl;
// Erase the 2nd to 4th elements
auto first = std::next(numbers.begin(), 1);
auto last = std::next(numbers.begin(), 4);
numbers.erase(first, last);
std::cout << "After deletion: ";
for(int n : numbers) std::cout << n << " ";
std::cout << std::endl;
return 0;
}
Expected Running Result:
原始: 1 2 3 4 5 6 7 After deletion: 1 5 6 7
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