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C++ Loops
course content

Course Content

C++ Loops

C++ Loops

1. While Loop
Introduction to While LoopSet Iterations with While LoopDo While LoopBreak and Continue KeywordsContinue Keyword Practice
2. For loop
Introduction to For LoopFor Loop Use CasesLoop PracticeModifying For Loop
3. Nested loops
Introduction to Nested LoopsNested While LoopsNested For Loops

book
Do While Loop

There is another loop called do while loop and as other loops it allows to get rid of code repetition. Understanding when to use each type of loop is essential in writing efficient and correct programs. But to do so at first we should know the difference between them.

  • While: checks the condition before running the loop. If the condition is false initially, the loop will not run at all;

  • Do-While: first runs the code inside it and then checks the condition. It guarantees that the code runs at least once, even if the condition is false initially.

cpp

main

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#include <iostream>

int main()
{
  do
  {
    std::cout << "Hello!" << std::endl;
  } while (false);
}

Note

Even though the condition is false, code inside the loop still executes, but only once.

A while loop can accomplish everything a do-while loop can, and if you need to ensure that a piece of code executes at least once, you can achieve that by duplicating it before the while loop. However, utilizing a do-while loop is typically a more straightforward and convenient approach in such cases.

h

while

h

do_while

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std::cout << "Some code to execute at least once!";

while (condition)
{
    std::cout << "Some code to execute at least once!";    
}
What happens if the condition in a `do-while` loop is never met?

What happens if the condition in a do-while loop is never met?

Select the correct answer

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Section 1. Chapter 3
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