Datasheet

will issue a warning if you assign a float to an int without an explicit cast. If you are certain that the

left-hand-side type is fully compatible with the right-hand side type, it’s okay to cast implicitly.

Operators

What good is a variable if you don’t have a way to change it? The table below shows the most common

operators used in C++ and sample code that makes use of them. Note that operators in C++ can be binary

(operate on two variables), unary (operate on a single variable), or even ternary (operate on three vari-

ables). There is only one ternary operator in C++ and it is covered in the next section, “Conditionals.”

Operator Description Usage

= Binary operator to assign the value on the right to int ;

the variable on the left. i = 3;

int j;

j = i;

Unary operator to negate the true/false (non-0/0) bool b = !true;

status of a variable. bool b2 = !b;

+ Binary operator for addition. int i = 3 + 2;

int j = i + 5;

int k = i + j;

Binary operators for subtraction, multiplication, int i = 5-1;

and division. int j = 5*2;

/ int k = j / i;

Binary operator for remainder of a division int remainder = 5 % 2;

operation. Also referred to as the mod operator.

++ Unary operator to increment a variable by 1. If the i++;

operator occurs before the variable, the result of ++i;

the expression is the unincremented value. If the

operator occurs after the variable, the result of the

expression is the new value.

-- Unary operator to decrement a variable by 1. i--;

--i;

Shorthand syntax for i = i + j i += j;

-= Shorthand syntax for i -= j;

*= i = i – j; i *= j;

/= i = i * j; i /= j;

%= i = i / j; i %= j;

i = i % j;

Takes the raw bits of one variable and performs a i = j & k;

bitwise “and” with the other variable. j &= k;

Takes the raw bits of one variable and performs a i = j | k;

bitwise “or” with the other variable. j |= k;

Chapter 1

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