sirine.ch - 1 year ago 1159

Java Question

I'm trying to solve this problem in HackerRank, but I get timed out error in some test cases. any suggestions?

the following is my code;

most test cases work, but others time out.

`public class Solution`

{

static int[] rotation(int[] arr)

{

int[] rot = new int[arr.length];

rot[0] = arr[arr.length - 1];

System.arraycopy(arr, 0, rot, 1, arr.length - 1);

return rot;

}

public static void main(String[] args)

{

Scanner in = new Scanner(System.in);

int n = in.nextInt();

int k = in.nextInt();

int q = in.nextInt();

int[] T = new int[n];

for (int i = 0; i < n; i++) {

T[i] = in.nextInt();

}

int[] indexes = new int[q];

for (int j = 0; j < q; j++) {

indexes[j] = in.nextInt();

}

in.close();

// Rotations

for (int ai = 0; ai < k; ai++) {

T = rotation(T);

}

// Queries

for (int qi = 0; qi < q; qi++) {

System.out.println(T[indexes[qi]]);

}

}

}

Answer Source

Maybe rotating the array in-place instead of creating a new one for each rotation?

```
static void rotation(int[] arr)
{
int temp = arr[arr.length - 1];
System.arraycopy(arr, 0, arr, 1, arr.length - 1);
arr[0] = temp;
}
```

And then later:

```
T = rotation(T);
```

Becomes:

```
rotation(T);
```

You could also optimize for the case where *k* is less than *n*, but I'll leave that as an exercise for you if you need it.