# std::list<T,Allocator>::splice

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< cpp‎ | container‎ | list

void splice( const_iterator pos, list& other ); | (1) |
void splice( const_iterator pos, list&& other ); | (1) | (since C++11)
void splice( const_iterator pos, list& other, const_iterator it ); | (2) |
void splice( const_iterator pos, list&& other, const_iterator it ); | (2) | (since C++11)
void splice( const_iterator pos, list& other, const_iterator first, const_iterator last); | (3) |
void splice( const_iterator pos, list&& other, const_iterator first, const_iterator last ); | (3) | (since C++11)

Transfers elements from one list to another.

No elements are copied or moved, only the internal pointers of the list nodes are re-pointed. The behavior is undefined if: get_allocator() != other.get_allocator(). No iterators or references become invalidated, the iterators to moved elements remain valid, but now refer into *this, not into `other`.

1) Transfers all elements from `other` into *this. The elements are inserted before the element pointed to by `pos`. The container `other` becomes empty after the operation. The behavior is undefined if `other` refers to the same object as *this.
2) Transfers the element pointed to by `it` from `other` into *this. The element is inserted before the element pointed to by `pos`.
3) Transfers the elements in the range `[first, last)` from `other` into *this. The elements are inserted before the element pointed to by `pos`. The behavior is undefined if `pos` is an iterator in the range `[first,last)`.

### Parameters

pos | - | element before which the content will be inserted
other | - | another container to transfer the content from
it | - | the element to transfer from `other` to *this
first, last | - | the range of elements to transfer from `other` to *this

### Return value

(none)

### Exceptions

Throws nothing.

### Complexity

1-2) Constant.

3) Constant if `other` refers to the same object as *this, otherwise linear in std::distance (first, last).

### Example

Run this code

    #include <iostream>
    #include <list>

    std::ostream& operator<<(std::ostream& ostr, const std::list<int>& list)
    {
        for (auto &i : list) {
            ostr << " " << i;
        }
        return ostr;
    }

    int main ()
    {
        std::list<int> list1 = { 1, 2, 3, 4, 5 };
        std::list<int> list2 = { 10, 20, 30, 40, 50 };

        auto it = list1.begin();
        std::advance(it, 2);

        list1.splice(it, list2);

        std::cout << "list1: " << list1 << "\n";
        std::cout << "list2: " << list2 << "\n";

        list2.splice(list2.begin(), list1, it, list1.end());

        std::cout << "list1: " << list1 << "\n";
        std::cout << "list2: " << list2 << "\n";
    }

Output:

    list1:  1 2 10 20 30 40 50 3 4 5
    list2:
    list1:  1 2 10 20 30 40 50
    list2:  3 4 5

### See also

merge | merges two sorted lists (public member function)
removeremove_if | removes elements satisfying specific criteria (public member function)

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