Summary: Expressions and Statements

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Summary: Expressions and Statements

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

Expressions

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)) .

Statements

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 statement  printf("%d\n", toes);  Control statement  while (toes < 20) toes = toes + 2;  Null statement  ; /* does nothing */  

Compound statements , or blocks , consist of one or more statements (which themselves can be compound) enclosed in braces. The following while statement is an example:

 while (years < 100) {     wisdom = wisdom + 1;     printf("%d %d\n", years, wisdom);     years = years + 1; } 

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