Iteration Statements (C++)
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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.
C++ provides four iteration statements — while, do, for, and range-based for. Each of these iterates until its termination expression evaluates to zero (false), or until loop termination is forced with a break statement. The following table summarizes these statements and their actions; each is discussed in detail in the sections that follow.
Iteration Statements
Statement | Evaluated At | Initialization | Increment |
---|---|---|---|
while |
Top of loop | No | No |
do | Bottom of loop | No | No |
for | Top of loop | Yes | Yes |
range-based for | Top of loop | Yes | Yes |
The statement part of an iteration statement cannot be a declaration. However, it can be a compound statement containing a declaration.