Understanding Precedence

As you were probably taught when you first learned arithmetic, operators have a precedence: rules dictating in what order calculations are made. These are important to understand because they can dramatically affect the end result.

Table 3.2 lists the order of precedence in C for the arithmetic operators, but it's probably easiest just to follow these three rules:

Multiplication and division take place before addition and subtraction.
Operators with the same precedence level are executed from left to right.
Use parentheses to guarantee your results.
Table 3.2. The precedence of operators from highest to lowest (those listed first will be executed first).
Rules of Precedence
++, --
+, - (Sign operators) ...

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