Circular Array Rotation | Editorial by coderboy

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Simply you can use the concept of vector (STL).

push_front the first element and then remove first element from the dequeue and do this for 'd' times.

Explanation :

let suppose an array of size 5 having elements [1, 2, 3, 4, 5] and number of rotations is 4.

Pseudo code :

```
for (int i = 0; i < k; i++)
    {
        v.push_front(v[n - 1]);
    }
```

When we perform d = 4 circular rotations, the array undergoes the following sequence of changes:

[5, 1, 2, 3, 4], [4, 5, 1, 2, 3], [3, 4, 5, 1, 2], [2, 3, 4, 5, 1]

In first iteration when i = 0 : After push_front operation dequeue 'v' will be [5, 1, 2, 3, 4,]

In second iteration when i = 1; firstly, dequeue will be [4, 5, 1, 2, 3].

In third iteration when i = 2; firstly, dequeue will be [3, 4, 5, 1, 2].

In third iteration when i = 3; firstly, dequeue will be [2, 3, 4, 5, 1].

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

int main()
{
    int n, k, q;
    cin >> n >> k >> q;

deque <int> v;
    int input;
    for (int i = 0; i < n; i++)
    {
        cin >> input;
        v.push_back(input);
    }
    for (int i = 0; i < k; i++)
    {
        v.push_front(v[n - 1]);
    }

for (int i = 0; i < q; i++)
    {
        int m;
        cin >> m;
        cout << v[m] << endl;
    }
}

```

Circular Array Rotation | Editorial by coderboy

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