Modulus

The modulus operation (also called modulo or mod) finds the remainder after dividing one integer by another. It's usually written as %.

For example, \frac{7}{5} is 1 with a remainder of 2. So 7 % 5 is 2.

It's commonly used to force a number into a certain range. For example, any number, when modded by 3 gives us an integer in the range 0..2:

>>> 0 % 3 0 >>> 1 % 3 1 >>> 2 % 3 2 >>> 3 % 3 0 >>> 4 % 3 1 >>> 5 % 3 2 >>> 6 % 3 0 >>> 7 % 3 1

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