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Rotating right an int array in C #?

I have a homework:

it is necessary to implement a function (RotateRight), which receives an INT array and a number:

int[] res = RotateRight(new int[] { 1, 2, 3, 4, 5, 6 }, 2);
//so then res will be {5,6,1,2,3,4}

and return the array after turning all the elements to the right in accordance with the number that was specified. In our case, 2.

And I have to do it efficiently in terms of memory size.

my best idea is:

if the number that was given is x, to use the new int [] tmpArray of size x to copy all the last elements of x into it. then use the for loop to shift the rest of the int to the right. Finally, copy the elements in tmpArray to the beginning of the original array.

Thanks in advance for any advice or help.

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4

Linq langage, IEnumerable, :

/// <summary>
/// Get c = a mod (b) with c in [0, b[ like the mathematical definition
/// </summary>
public static int MathMod(int a, int b)
{
    int c = ((a % b) + b) % b;
    return c;
}
public static IEnumerable<T> ShiftRight<T>(IList<T> values, int shift)
{
    for (int index = 0; index < values.Count; index++)
    {
        yield return values[MathMod(index - shift, values.Count)];
    }
}

:

[TestMethod]
public void TestMethod1()
{
    var res = ShiftRight(new [] { 1, 2, 3, 4, 5, 6 }, 2).ToArray();
    Assert.IsTrue(res.SequenceEqual(new[] { 5, 6, 1, 2, 3, 4 }));
}
+5

, , , ? , XOR, i.e:

var a = 2096;
var b = 842390;

a ^= b;
b ^= a;
a ^= b;

.

, :

    public static void RotateRight(int[] input, int right)
    {
        for (var i = 0; i < right; i += 1)
        {
            RotateRightOne(input);
        }
    }

    public static void RotateRightOne(int[] input)
    {
        var last = input.Length - 1;
        for (var i = 0; i < last; i += 1)
        {
            input[i] ^= input[last];
            input[last] ^= input[i];
            input[i] ^= input[last];
        }
    }

:

    var arr = new[] {1, 2, 3, 4, 5, 6};
    RotateRight(arr, 2);

Servy,

+1

#, ++, , (rotate) , , (rotate_k) 2*n n. , k n - k % n, .

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

void
rotate (size_t k, std::vector<int> &a) {
    size_t n = a.size();
    k = n - k % n;

    size_t m = n;

    size_t i = 0;
    while (m > 0) {
        int t = a[i];
        size_t j = i;
        while (i != (j + k) % n) {
            a[j] = a[(j + k) % n];
            j = (j + k) % n;
            --m;
        }
        a[j] = t;
        --m;
        ++i;
    }
}

void
rotate_k (size_t k, std::vector<int> &a) {
    size_t n = a.size();

    k = n - k % n;

    std::reverse (a.begin(), a.end());
    std::reverse (a.begin(), a.begin() + n - k);
    std::reverse (a.begin() + n - k, a.end());
}

int
main () {
    std::vector<int> a = { 1, 2, 3, 4, 5, 6, 7, 8, 9};
    rotate (12, a);

    for (auto i : a)
        std::cout << i << " ";

    std::cout << std::endl;
}
0

k , k . :

for(int i=0;i<a.Length;i++){
        rotated[(k+i)%(a.Length)]=a[i];
    }
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