How to Rotate Items in a Vector in C++ - Step by Step Examples

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How to Rotate Items in a Vector in C++ ?

Answer

To rotate items in a vector in C++, you can use the `std::rotate` algorithm provided by the algorithm header.

✐ Examples

1 Rotate Items in Vector to the Left

In this example,

First, you include the necessary header files: vector for vectors and algorithm for the rotate algorithm.
Next, you define a vector containing the elements you want to rotate.
Then, you specify the number of positions to rotate the items to the left.
Finally, you use the `std::rotate` algorithm with appropriate iterators to rotate the items to the left by the specified number of positions.

C++ Program

#include <iostream>
#include <vector>
#include <algorithm>

int main() {
    // Define a vector containing elements
    std::vector<int> vec = {1, 2, 3, 4, 5};

    // Specify the number of positions to rotate the items to the left
    int rotate_by = 2;

    // Rotate the items to the left by the specified number of positions
    std::rotate(vec.begin(), vec.begin() + rotate_by, vec.end());

    // Print the rotated vector
    std::cout << "[ ";
    for (int i : vec) {
        std::cout << i << " ";
    }
    std::cout << "]" << std::endl;
    return 0;
}

Output

[3 4 5 1 2]

2 Rotate Items in Vector to the Right

In this example,

Include the necessary header files: vector for vectors and algorithm for the rotate algorithm.
Define a vector containing the elements you want to rotate.
Specify the number of positions to rotate the items to the right.
Use the `std::rotate` algorithm with appropriate iterators to rotate the items to the right by the specified number of positions.

C++ Program

#include <iostream>
#include <vector>
#include <algorithm>

int main() {
    // Define a vector containing elements
    std::vector<int> vec = {1, 2, 3, 4, 5};

    // Specify the number of positions to rotate the items to the right
    int rotate_by = 2;

    // Rotate the items to the right by the specified number of positions
    std::rotate(vec.rbegin(), vec.rbegin() + rotate_by, vec.rend());

    // Print the rotated vector
    std::cout << "[ ";
    for (int i : vec) {
        std::cout << i << " ";
    }
    std::cout << "]" << std::endl;
    return 0;
}

Output

[4 5 1 2 3]

Summary

In this tutorial, we learned How to Rotate Items in a Vector in C++ language with well detailed examples.

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How to Rotate Items in a Vector in C++ - Step by Step Examples

How to Rotate Items in a Vector in C++ ?

Answer

✐ Examples

1 Rotate Items in Vector to the Left

C++ Program

Output

2 Rotate Items in Vector to the Right

C++ Program

Output

Summary

More C++ Vectors Tutorials