Previous post: Java Tips for Beginners (1) : Data Types

I will add two tips from module 1.

### Mixed data types

Pay attention when using mixed data types: If you use two data types in one expression, it will automatically take the more general type. Double is the more general type compared to Int.

##### Example 1:

double avg = 2 is allowed; int avg = 3.2 is not allowed.

##### Example 2:

int avg = (int) 3.2 is allowed The conversion requires the explicit cast, which will drop decimal places and get avg = 3.

##### Example 3:

```
int avg = (3+4)/2
will get avg = 3
```

##### Example 4:

```
Double avg = (5+6)/2
will get avg = 5.0, because the right-hand side is computed first
```

##### Example 5:

`Double avg = (double)(5+6)/2`

In this case (double) 11 will be computed first,

so this time you will get avg = 5.5

### The ternary operator

source: http://www.cafeaulait.org/course/week2/43.html

`max = (a > b) ? a : b;`

is equivalent with

```
if (a > b) {
max = a;
}
else {
max = b;
}
```

**More examples:**

http://alvinalexander.com/java/edu/pj/pj010018

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