/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
 
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		String s = "serendipia";
        int k = 3;
        String[] substringsArray = new String[s.length() - k + 1];
 
        // make sure you don't go beyond the String's length
        for (int i = 0; (i+k) <= s.length(); i++){
            substringsArray[i] = s.substring(i,i+k);
        }
 
        System.out.println(Arrays.toString(substringsArray));
	}
}

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