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DIFFERENCE BETWEEN WHILE AND DO-WHILE LOOPS
The following are the major differences between while and do-while loops:
1. Pre-Test vs Post-Test:
The while loop is a pre-test (or top-test) loop, meaning the condition is checked first
before entering the loop body.
The do-while loop is a post-test (or bottom-test) loop, meaning the loop body executes
first, and then the condition is checked.
2. Minimum Iterations:
In a while loop, the minimum number of iterations is zero because the condition is
tested before executing the loop body.
In a do-while loop, the minimum number of iterations is one, as the loop body executes
at least once, even if the condition is false.
3. Interchangeability:
while and for loops are interchangeable in most situations.
do-while loops, however, cannot always be replaced by a for loop, as they guarantee at
least one execution of the loop body.
JUMP STATEMENTS
Jump statements help to control the flow of a program by making it jump to a different part of
the code. These statements allow the program to exit loops, skip iterations, or jump to a specific
location in the code. C++ offers four jump statements — break, continue, return and goto —
which are used within the loop.
The break Statement
The break statement is used to exit a loop immediately and transfer control to the statement
after the loop. It halts the execution of the loop when a specific condition is met. A single break
statement only exits one loop at a time. If used inside a nested loop, it will break only the
innermost loop where it appears. The syntax of the break statement is shown below:
while(condition)
{
if(conditional_expression)
{
break;
}
}
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