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## += , -= , *= , /= , %=

#### Description

Perform a mathematical operation on a variable with another constant or variable. The += (et al) operators are just a convenient shorthand for the expanded syntax, listed below.

#### Syntax

x += y; // equivalent to the expression x = x + y;
x -= y; // equivalent to the expression x = x - y;
x *= y; // equivalent to the expression x = x * y;
x /= y; // equivalent to the expression x = x / y;
x %= y; // equivalent to the expression x = x % y;

#### Parameters

x: any variable type

y: any variable type or constant

#### Examples

x = 2;
x += 4; // x now contains 6
x -= 3; // x now contains 3
x *= 10; // x now contains 30
x /= 2; // x now contains 15
x %= 5; // x now contains 0

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