Note how this differs from the
while
loop: the decision comes at the end, not the
beginning.
do...while
loops are for when you know you always want to execute the
body of the loop at least once (if the condition in a
while
loop starts off as falsy, it
won’t even run once). Now in JavaScript:
let
remaining
=
totalBet
;
do
{
let
bet
=
rand
(
1
,
remaining
);
let
face
=
randFace
();
bets
[
face
]
=
bets
[
face
]
+
bet
;
remaining
=
remaining
-
bet
;
}
while
(
remaining
>
0
);
for Loop
Thomas has now placed all his bets! Time to roll the dice.
The
for
loop is extremely flexible (it can even replace a
while
or
do...while
loop),
but it’s best suited for those times when you need to do things a fixed number of
times (especially when you need to know which step you’re on), which makes it ideal
for rolling a fixed number of dice (three, in this case). Let’s start with our “roll dice”
flowchart, shown in
.
Figure 4-5. Crown and Anchor simulation: roll dice flowchart
64 | Chapter 4: Control Flow
