If we ever want to exit a loop before it finishes all its iterations or want to skip one of the iterations, we can use the break
and continue
keywords.
The break
keyword is used to exit, or break, a loop. Once break
is executed, the loop will stop iterating. For example:
for (int i = 0; i < 10; i++) { System.out.println(i); if (i == 4) { break; } }
Even though the loop was set to iterate until the condition i < 10
is false
, the above code will output the following because we used break
:
0 1 2 3 4
The continue
keyword can be placed inside of a loop if we want to skip an iteration. If continue
is executed, the current loop iteration will immediately end, and the next iteration will begin. We can use the continue
keyword to skip any even valued iteration:
int[] numbers = {1, 2, 3, 4, 5}; for (int i = 0; i < numbers.length; i++) { if (numbers[i] % 2 == 0) { continue; } System.out.println(numbers[i]); }
This program would output the following:
1 3 5
In this case, if a number is even, we hit a continue
statement, which skips the rest of that iteration, so the print statement is skipped. As a result, we only see odd numbers print.
Keep Reading: AP Computer Science A Students
Loops can exist all throughout our code - including inside a method. If the return
keyword was executed inside a loop contained in a method, then the loop iteration would be stopped and the method/constructor would be exited.
For example, we have a method called checkForJacket()
that takes in an array of String
s. If any of the elements are equivalent to the String
value "jacket"
, the method will return true
:
public static boolean checkForJacket(String[] lst) { for (int i = 0; i < lst.length; i++) { System.out.println(lst[i]); if (lst[i] == "jacket") { return true; } } return false; } public static void main(String[] args) { String[] suitcase = {"shirt", "jacket", "pants", "socks"}; System.out.println(checkForJacket(suitcase)); }
As soon as an element equals "jacket"
, return true;
is executed. This causes the loop to stop and the compiler to exit checkForJacket()
. Running this code would output the following:
shirt jacket true
Instructions
Take a look at the for
loop in the code editor. It starts its iteration at 0
and continues to iterate until i < 100
is false
.
Inside the loop, create a condition that checks if i
is not divisible by 5
. If the condition is true
, skip the iteration. Outside the condition statement, print i
. The final solution should not contain an else
statement.
The only numbers that should be printed are those that are divisible by 5!