The do-while Loop

  • The last of C++’s loops is the do-while. Unlike the for and the while loops, in which the condition is tested at the top of the loop, the do-while loop checks its condition at the bottom of the loop.
  • This means that a do-while loop will always execute at least once.
  • Unlike for and while loops, which test the loop condition at the top of the loop, the do...while loop in C programming checks its condition at the bottom of the loop.

 

Syntax

do
{
  statement(s);
}
while(condition);

 

Flow Diagram

do...while loop in C

Example

// divdo.cpp 
// demonstrates DO loop 
#include using namespace std; 

int main() 
  { 
   long dividend, divisor; 
   char ch; 

   do //start of do loop 
    { //do some processing 
    cout > dividend;
    cout > divisor;
    cout > ch;
 }
 while( ch != ‘n’ ); //loop condition
 return 0; 
} 

Output

 Enter dividend: 11
 Enter divisor: 3
 Quotient is 3,
 remainder is 2
 Do another? (y/n): n