5.6 Iteration Statements

Iteration statements cause statements (or compound statements) to be executed zero or more times, subject to some loop-termination criteria. When these statements are compound statements, they are executed in order, except when either the break statement or the continue statement is encountered. (For a description of these statements, see “The break Statement” and “The continue Statement”.)

C++ provides three iteration statements—while, do, and for. Each of these iterates until its termination expression evaluates to zero (false), or until loop termination is forced with a break statement. Table 5.2 summarizes these statements and their actions; each is discussed in detail in the sections that follow.

Table 5.2 C++ Iteration Statements

Syntax

iteration-statement:
while (expression)statement
dostatementwhile (expression) ;
for (for-init-statement expressionopt;expressionopt)statement

for-init-statement:
expression-statement
declaration-statement

The statement part of an iteration statement cannot be a declaration. However, it can be a compound statement containing a declaration.