Thread: Nested For Loops

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Sorry wrong code, edited now.

Thats it now,

I just need to know what happens in nested loops, not that particular program, I mean if a loop loops something 10 times and a loop outside it loops 5 times does this mean that the inside is looped 50 times?

The compiler reads from top-down, so it will enter the outer for-loop and executes the code inside of it (i.e. inner for-loop). Once the inner for-loop has finished iterating, the outer for-loop iterates once more and executes the inner for-loop again. This continues until the outer for-loop has finished iterating.

Here's a very simple example I made on the spot:

 
import java.util.Scanner;
 
public class something {
 
     public static void main(String[] args) {
 
           Scanner input = new Scanner(System.in);
 
           while(true) {
 
                System.out.println("Enter 'play' to play or 'no' to not play");
                String data = input.nextLine();
 
                if(data.equalsIgnoreCase("no")) {
                     break;
                }
 
                while(data.equalsIgnoreCase("play")) {
                     // more code
                }
           }
      }
}

If the user enters "no", then the outer loop ends and the code within the inner loop is never executed. On the other hand, if the user enters, "play", then the code within the inner loop is executed. If the user enters anything else, then the inner loop is not executed and since there is no else statement with the if-statement, the outer loop re-iterates until the user enters valid input.

Not all programs will use nested loops, you only have nested loops in your program if it requires them. There generally are many ways of writing code to achieve the same functionality.