Marie Mirbekian - 6 months ago 24

Java Question

Output that I want: 10 20 30 40 50..............

Output that I get: 0

`public class HelloWorld`

{

public static void main(String[] args)

{

final int n = 50;

int i= 0;

while(i <= n && i % 10 == 0 )

{

System.out.println(i);

i++;

}

}

}

Answer

```
while(i <= n && i % 10 == 0 )
```

This is the continuation condition which is two expressions connected by logical-and `&&`

.

That means *both* must be true for the whole thing to be true.

Now work out the two sub-expressions for when `i`

becomes `1`

. The first will be true but not so the second (`1`

is not a multiple of `10`

), meaning the loop will exit at that point. That explains why you're only seeing `0`

.

To fix it, you need to separate the two sub-expressions since the loop control depends *only* on the first. However, you still only want *printing* to happen for multiples of ten (the second).

So, assuming as per your desired output `10 20 30 40 50`

, you *don't* want `0`

as one of the outputs (despite it being, after all, a multiple of 10), the following pseudo-code will do the trick:

```
set n to 50, i to 1
while i is less than or equal to n:
if the remainder when i is divided by 10 is 0:
output i
increment i
```

If you *do* want `0`

included in the output, simply set `i`

to `0`

initially, and you'll see `0 10 20 30 40 50`

.

I've left the code above as pseudo-code on the assumption this is classwork of some description - it should be relatively easy to turn that into any procedural language.