I am writing a simple program to calculate the average of a set of numbers. You get the numbers using Scanner, so I am using while loop with .hasNext() as a condition. However the loop is infinite.
Is it possible to break out of it without writing some certain word like "stop" in the input?
public class main {
public static void main(String[] args){
Scanner Input = new Scanner(System.in);
int count = 0;
int temp;
int sum = 0;
while(Input.hasNextInt()){
count++;
temp = Input.nextInt();
sum += temp;
System.out.println(temp);
System.out.println(count);
} // End of while
double average = sum / count;
System.out.println("The average is: " + average);
} // End of method main
}
解决方案
The break; statement can be sued to... well... break out of an iteration. And by iteration I mean you can get out of a for too, for example.
You have to define WHEN do you want to break out of the iteration and then do something like this:
while(Input.hasNextInt(Input)){
if(condition())
break;
count++;
temp = Input.nextInt();
sum += temp;
System.out.println(temp);
System.out.println(count);
}
Otherwise, you can make an auxiliary method that defines if the iteration should keep on going, like this one:
private boolean keepIterating(Scanner in) {
boolean someOtherCondition = //define your value here that must evaluate to false
//when you want to stop looping
return Input.hasNextInt() && someOtherCondition;
}
Method that you will have to invoke in your while:
while(keepIterating()){
count++;
temp = Input.nextInt();
sum += temp;
System.out.println(temp);
System.out.println(count);
}