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Java Nesting Loops

Posted by Erik Lopez
Erik Lopez
415 Points

How would you do a nested for loop if you wanted to randomize the combinations between each of the two arrays?

For instance, if you didn't want a list of all the combinations starting with caramel, then wanted each of the combinations with cinnamon, then watermelon, et al. Instead, you wanted a randomized version where any one of the four sweets started and any one of the four savory was appended to a sweet. What would that look like in code?

Marek Mikos
Marek Mikos
314 Points
Marek Mikos
Marek Mikos
314 Points

Hi,

I'm new to java so my solution might not be the best, but I have come up with following solution. I have converted array to list and the used shuffle from Collection: (example with odd and even numbers)

import java.io.Console; import java.util.*; public class nestedForLoops {

public static void main (String args[]) {
    Console console = System.console();

    String [] evenNumbers = {"2","4","6","8","10"};
    String [] oddNumbers = {"1","3","5","7","9"};

    //converting to list
    List<String> listEven = Arrays.asList(evenNumbers);
    List<String> listOdd = Arrays.asList(oddNumbers);

    // Shuffling list elements
    Collections.shuffle(listEven);
    Collections.shuffle(listOdd);

    for (String even : listEven)
    {
        for (String odd : listOdd)
        {
            console.printf("%s a %s %n", even, odd);
        }       
    }
}

}