*Extensions* provide a more in-depth overview of various topics. Here, I present a more in-depth discussion behind primitive data types.

# Type int

As mentioned before, integers consist of individual digits. You can prefix it with a minus sign (a hyphen) to make it negative. You cannot put spaces, commas, or periods inside ints.

When dividing an integer by another, *integer division* occurs. In this case, the remainder of the division is dropped. Therefore, the result of 8/5 is 1, not 1.6. A practical use of this is as follows:

```
int number = 1234;
int thousands = number / 1000;
NSLog ("@The thousands place of %d is %d.", number, thousands);
```

The output of the code above is

**The thousands place of 1234 is 1.**

In contrast, the *modulus* operator (%) is used to derive the exact remainder of integer division. Therefore, 8 % 5 = 3.

Extending the above example,

```
int number = 1234;
int thousands = number / 1000;
NSLog ("@The thousands place of %d is %d.", number, thousands);
int hundreds = (number % 1000) / 100;
NSLog ("@The hundreds place of %d is %d.", number, hundreds);
int tens = ((number % 1000) % 100) / 10;
NSLog (@"The tens place of %d is %d.", number, tens);
int ones = (((number % 1000) % 100) % 10);
NSLog (@"The ones place of %d is %d.", number, ones);
```

The output of the code is

**The thousands place of 1234 is 1.
The hundreds place of 1234 is 2.
The tens place of 1234 is 3.
The ones place of 1234 is 4.**

The code above is rather involved, but try to figure it out. Remember, the modulus operator extracts the remainder of the division that could have been placed in its place.

## Ethan

/ October 17, 2010Good tutorial so far. I have never really understood a practical use of the modulus operator. So simple!!!! Thanks! Keep going!

-Ethan

## inspire48

/ October 17, 2010You’re welcome! Thanks for stopping by. I have a lot more stuff to put, I just need to find time.

## inspire48

/ October 19, 2010Another practical use of the modulus operatorâ€”to limit the results of an operation:

https://cupsofcocoa.wordpress.com/2010/10/19/extension-3-a-b-c/

## jeff

/ August 10, 2012another common use is to determine if number is even or odd:

for(int i=0;i<10;i++){

NSLog(@"%d is %s", i, (i % 2==0 ? "even" : "odd"));

}

This example also uses the ternary operator, which is short-hand for an if/else.