queue::swap() in C++ STL
Last Updated :
08 Sep, 2022
Queue is also an abstract data type or a linear data structure, which follows a particular order in which the operations are performed. The order is First In First Out (FIFO). In a FIFO data structure, the first element added to the queue will be the first one to be removed. queue::swap() swap() function is used to exchange the contents of two queues but the queues must be of same type, although sizes may differ.
Syntax:
queue1.swap(queue2)
OR
swap(queue1, queue2)
Parameters:
queue1 is the first queue object.
queue2 is the second queue object.
Return value: None
Examples:
Input : queue1 = {1, 2, 3, 4}
queue2 = {5, 6, 7, 8}
queue1.swap(queue2);
Output : queue1 = {5, 6, 7, 8}
queue2 = {1, 2, 3, 4}
Input : queue1 = {'a', 'b', 'c', 'd', 'e'}
queue2 = {'f', 'g', 'h', 'i'}
queue1.swap(queue2);
Output : queue1 = {'f', 'g', 'h', 'i'}
queue2 = {'a', 'b', 'c', 'd', 'e'}
Errors and Exceptions 1. It throws an error if the queues are not of the same type. 2. It has a basic no exception throw guarantee otherwise.
CPP
#include <bits/stdc++.h>
using namespace std;
int main()
{
queue< char > queue1, queue2;
int v = 96;
for ( int i = 0; i < 5; i++) {
queue1.push(v + 1);
v++;
}
for ( int i = 0; i < 4; i++) {
queue2.push(v + 1);
v++;
}
queue1.swap(queue2);
cout << "queue1 = ";
while (!queue1.empty()) {
cout << queue1.front() << " ";
queue1.pop();
}
cout << endl << "queue2 = ";
while (!queue2.empty()) {
cout << queue2.front() << " ";
queue2.pop();
}
return 0;
}
|
Output:
queue1 = f g h i
queue2 = a b c d e
Time complexity: Linear i.e. O(n)
Auxiliary Space : O(n) because using queue
Share your thoughts in the comments
Please Login to comment...