Section IV—Expressions, Statements, and Program Flow

Summary: Expressions and Statements

In C, expressions represent values, and statements represent instructions to the computer.


An expression is a combination of operators and operands. The simplest expression is just a constant or a variable with no operator, such as 22 or beebop. More complex examples are 55 + 22 and vap = 2 * (vip + (vup = 4)).


A statement is a command to the computer. Any expression followed by a semicolon forms a statement, although not necessarily a meaningful one. Statements can be simple or compound. Simple statements terminate in a semicolon, as shown in these examples:

Declaration statement int toes;
Assignment statement toes = 12;
Function call ...

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