mirror of
https://codeberg.org/andyscott/exercism.git
synced 2024-11-14 07:10:48 -05:00
95 lines
No EOL
3.2 KiB
Markdown
95 lines
No EOL
3.2 KiB
Markdown
# Pacman Rules
|
|
|
|
Welcome to Pacman Rules on Exercism's C++ Track.
|
|
If you need help running the tests or submitting your code, check out `HELP.md`.
|
|
If you get stuck on the exercise, check out `HINTS.md`, but try and solve it without using those first :)
|
|
|
|
## Introduction
|
|
|
|
Booleans in C++ are represented by the `bool` type.
|
|
A `bool` is either `true` or `false`.
|
|
|
|
## Logical Operators
|
|
|
|
C++ supports three boolean operators: `!` (NOT), `&&` (AND), and `||` (OR).
|
|
You can also use the alternative versions `not`, `and`, and `or`.
|
|
|
|
```cpp
|
|
true || false // => true
|
|
true && false // => false
|
|
!true // => false
|
|
not false // => true
|
|
```
|
|
|
|
## Precedence
|
|
|
|
The three boolean operators each have different _operator precedence_.
|
|
As a consequence, they are evaluated in this order: `!` first, `&&` second, and finally `||`.
|
|
If you want to force a different ordering, you can enclose a boolean expression in parentheses (ie. `()`), as the parentheses have even higher operator precedence.
|
|
|
|
```cpp
|
|
!true && false // => false
|
|
!(true and false) // => true
|
|
```
|
|
|
|
~~~~exercism/advanced
|
|
## Conversion
|
|
|
|
If you use `true` or `false` in a place where a number is expected, they will be converted to `1` and `0` respectively.
|
|
If you use a number in a Boolean operation, everything except `0` is treated as `true` - even negative values.
|
|
|
|
```cpp
|
|
!true && 0.0 // => false
|
|
true + true + false // => 2
|
|
```
|
|
~~~~
|
|
|
|
## Instructions
|
|
|
|
In this exercise, you need to translate some rules from the classic game Pac-Man into C++ functions.
|
|
|
|
You have four rules to translate, all related to the game states.
|
|
|
|
> Don't worry about how the arguments are derived, just focus on combining the arguments to return the intended result.
|
|
|
|
## 1. Define if Pac-Man eats a ghost
|
|
|
|
Define the `can_eat_ghost` function that takes two arguments (_if Pac-Man has a power pellet active_ and _if Pac-Man is touching a ghost_) and returns a boolean value if Pac-Man is able to eat the ghost. The function should return true only if Pac-Man has a power pellet active and is touching a ghost.
|
|
|
|
```cpp
|
|
can_eat_ghost(false, true);
|
|
// => false
|
|
```
|
|
|
|
## 2. Define if Pac-Man scores
|
|
|
|
Define the `scored` function that takes two arguments (_if Pac-Man is touching a power pellet_ and _if Pac-Man is touching a dot_) and returns a boolean value if Pac-Man scored. The function should return true if Pac-Man is touching a power pellet or a dot.
|
|
|
|
```cpp
|
|
scored(true, true);
|
|
// => true
|
|
```
|
|
|
|
## 3. Define if Pac-Man loses
|
|
|
|
Define the `lost` function that takes two arguments (_if Pac-Man has a power pellet active_ and _if Pac-Man is touching a ghost_) and returns a boolean value if Pac-Man loses. The function should return true if Pac-Man is touching a ghost and does not have a power pellet active.
|
|
|
|
```cpp
|
|
lost(false, true);
|
|
// => true
|
|
```
|
|
|
|
## 4. Define if Pac-Man wins
|
|
|
|
Define the `won` function that takes three arguments (_if Pac-Man has eaten all of the dots_, _if Pac-Man has a power pellet active_, and _if Pac-Man is touching a ghost_) and returns a boolean value if Pac-Man wins. The function should return true if Pac-Man has eaten all of the dots and has not lost based on the arguments defined in part 3.
|
|
|
|
```cpp
|
|
won(false, true, false);
|
|
// => false
|
|
```
|
|
|
|
## Source
|
|
|
|
### Created by
|
|
|
|
- @vaeng |