The do…while() statement has the following syntax:
do statement_body while( continuation_expression );
The only difference between this statement and the while()_statement is that, in thedo…while() statement, statement_body is executed beforecontinuation_expression is evaluated. If the continuation_expression result is true, the loop repeats. When continuation_expression evaluates to false, the loop ends. Note also the terminating semicolon. If the continuation_expressioninitially evaluates to false, the statement_body loop is executed once and only once.
Returning again to Gauss's problem, the similarities to the while()_ statement are clear. In fact, for this problem, there is a very little difference between the while()_ and do…while() statements.
The sumNviaDoWhile() function in the gauss_loop.c program can be seen in the following code block: