Java Program for Queries for rotation and Kth character of the given string in constant time

// Java implementation of the above approach
import java.util.*;
class GFG 
{
static int size = 2;

// Function to perform the required
// queries on the given string
static void performQueries(String str, int n,
                           int queries[][], int q)
{

    // Pointer pointing to the current 
    // starting character of the string
    int ptr = 0;

    // For every query
    for (int i = 0; i < q; i++) 
    {

        // If the query is to rotate the string
        if (queries[i][0] == 1)
        {

            // Update the pointer pointing to the
            // starting character of the string
            ptr = (ptr + queries[i][1]) % n;
        }
        else 
        {
            int k = queries[i][1];

            // Index of the kth character in the
            // current rotation of the string
            int index = (ptr + k - 1) % n;

            // Print the kth character
            System.out.println(str.charAt(index));
        }
    }
}

// Driver code
public static void main(String[] args)
{
    String str = "abcdefgh";
    int n = str.length();

    int queries[][] = { { 1, 2 }, { 2, 2 }, 
                        { 1, 4 }, { 2, 7 } };
    int q = queries.length;

    performQueries(str, n, queries, q);
}
} 

// This code is contributed by 29AjayKumar