valarray shift() in C++

The shift() function is defined in valarray header file. This function returns a new valarray of the same size with elements whose positions are shifted by n elements. If n is negative, right-shift is applied, if n is positive left-shift is applied.

Syntax:

valarray shift (int n) const;

Parameter: This method accepts a mandatory parameter n which represents the number of element to shift.

Returns: This function returns the new valarray after shifting elements.

Below programs illustrate the above function:

Example 1:-

// C++ program to demonstrate
// example of shift() function.

#include <bits/stdc++.h>
using namespace std;

int main()
{
    // Initializing valarray
    valarray<int> varr = { 3, 2, 5, 4, 1 };

    // Declaring new valarray
    valarray<int> varr1;

    // using shift() to shift elements to left
    // shifts valarray by 3 position
    varr1 = varr.shift(3);

    // Displaying elements of valarray after shifting
    cout << "The new valarray after shifting is = ";

    for (int& x : varr1)
        cout << x << " ";

    cout << endl;

    return 0;
}

Output:

The new valarray after shifting is = 4 1 0 0 0

Example 2:-

// C++ program to demonstrate
// example of shift() function.

#include <bits/stdc++.h>
using namespace std;

int main()
{
    // Initializing valarray
    valarray<int> varr = { 3, 2, 5, 4, 1 };

    // Declaring new valarray
    valarray<int> varr1;

    // using shift() to shift elements to right
    // shifts valarray by 2 position
    varr1 = varr.shift(-2);

    // Displaying elements of valarray after shifting
    cout << "The new valarray after shifting is = ";

    for (int& x : varr1)
        cout << x << " ";

    cout << endl;

    return 0;
}

Output:

The new valarray after shifting is = 0 0 3 2 5