Sunday, January 8, 2012

Writing Conditional and Loop Statements

By default, statements are executed once in sequence, beginning with the first statement of main() . In the
preceding section, we had a peek at the if statement. The if statement allows us to execute conditionally
one or a sequence of statements based on the truth evaluation of an expression. An optional else clause
allows us to test multiple truth conditions. A looping st atement allows us to repeat one or a sequence of
statements based on the truth evaluation of an expression. The following pseudo-code program makes use
of two looping statements ( #1 and #2), one if statement ( #5), one if-else statement ( #3), and a
second conditional statement called a switch statement ( #4).

The condition expression of the if statement must be within parentheses. If it is true, the statement
immediately following the if statement is executed:

If multiple statements must be executed, they must be enclosed in curly braces following the if statement
(this is called a statement block):
Running Codes
// Pseudo code: General logic of our program
while the user wants to guess a sequence
{ #1
display the sequence
while the guess is not correct and
the user wants to guess again
{ #2
read guess
increment number-of-tries count
if the guess is correct
{ #3
increment correct-guess count
set got_it to true
} else {
express regret that the user has guessed wrong
generate a different response based on the
current number of guesses by the user // #4
ask the user if she wants to guess again
read response
if user says no // #5
set go_for_it to false
}
}
}


// #5
if (usr_rsp == 'N' || usr_rsp == 'n')
go_for_it = false;


//#3
if (usr_guess == next_elem)
{ // begins statement block
num_right++;
got_it = true;
} // ends statement block


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