Introduction to Programming/Answers to the exercises

Checking An Error Condition
In programming there is rarely one right answer, but for something this simple, your answer should look something like this:

if (divisor != 0) {       quotient = dividend / divisor; }   else {       ReportErrorMessage; }

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Fibonacci Numbers
int fN = 0; int fNplus1 = 1; int counter = 0;

while (counter < 11) {   fNplus2 = fN + fNplus1; print fN;

fN = fNplus1; fNplus1 = fNplus2; counter += 1; }

A variation, in Perl:

my $counter = 0; my $F = 1; my $prev_F = 0;

while( $counter < 10 ) { print $F. "\n"; my $x = $F; $F = $prev_F + $F; $prev_F = $x;

$counter++; }

Python 3 version :

f = 1 prevF = 0 counter = 0

while counter < 10:    #While loop. What's underneath it runs until counter becomes (counter < 10).

counter += 1 	#You can write this line also as "counter = counter + 1". It assigns 'counter' variable to itself increased by one. print(prevF) prevF += f counter += 1	#We add one to 'counter' variable before each character is printed on screen. print(f) f += prevF

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