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Instructions

Test suite

Solution

Write a function that returns the earned points in a single toss of a Darts game.

Darts is a game where players throw darts to a target.

In our particular instance of the game, the target rewards with 4 different amounts of points, depending on where the dart lands:

- If the dart lands outside the target, player earns no points (0 points).
- If the dart lands in the outer circle of the target, player earns 1 point.
- If the dart lands in the middle circle of the target, player earns 5 points.
- If the dart lands in the inner circle of the target, player earns 10 points.

The outer circle has a radius of 10 units (This is equivalent to the total radius for the entire target), the middle circle a radius of 5 units, and the inner circle a radius of 1. Of course, they are all centered to the same point (That is, the circles are concentric) defined by the coordinates (0, 0).

Write a function that given a point in the target (defined by its `real`

cartesian coordinates `x`

and `y`

), returns the correct amount earned by a dart landing in that point.

It's possible to submit an incomplete solution so you can see how others have completed the exercise.

To run the test suite, execute one of the following commands:

```
tclsh darts.test # Will stop testing after the first failure.
RUN_ALL=1 tclsh darts.test # Will run all tests and report all failures.
```

The exercism/tcl repository on GitHub is the home for all of the Tcl exercises on Exercism.

If you have feedback about an exercise, or want to help implementing a new one, head over there and create an issue. We'll do our best to help you!

Inspired by an exercise created by a professor Della Paolera in Argentina

```
#!/usr/bin/env tclsh
set version 2.2.0
package require tcltest
namespace import ::tcltest::*
source "darts.tcl"
proc fail_fast {} {
return [expr {
![info exists ::env(RUN_ALL)]
|| [string is boolean -strict $::env(RUN_ALL)]
&& !$::env(RUN_ALL)
}]
}
proc failed {} {
return [expr {$::tcltest::numTests(Failed) > 0}]
}
if {[fail_fast]} {
proc test args {
if {[failed]} {::tcltest::configure -skip *}
uplevel [list ::tcltest::test {*}$args]
}
}
proc cleanupTests {} {
set failed [failed]
uplevel 1 ::tcltest::cleanupTests
if {$failed} {exit 1}
}
if {$::argv0 eq [info script]} {
set cases {
darts-1 "Missed target" -9 9 0
darts-2 "On the outer circle" 0 10 1
darts-3 "On the middle circle" -5 0 5
darts-4 "On the inner circle" 0 -1 10
darts-5 "Exactly on centre" 0 0 10
darts-6 "Near the centre" -0.1 -0.1 10
darts-7 "Just within the inner circle" 0.7 0.7 10
darts-8 "Just outside the inner circle" 0.8 -0.8 5
darts-9 "Just within the middle circle" -3.5 3.5 5
darts-10 "Just outside the middle circle" -3.6 -3.6 1
darts-11 "Just within the outer circle" -7.0 7.0 1
darts-12 "Just outside the outer circle" 7.1 -7.1 0
darts-13 "Asymmetric position between the inner and middle circles" 0.5 -4 5
}
foreach {name description x y value} $cases {
test $name $description -body {
score $x $y
} -returnCodes ok -result $value
}
cleanupTests
}
```

```
proc score {x y} {
set distance [expr {hypot($x, $y)}]
if {$distance <= 1} {return 10}
if {$distance <= 5} {return 5}
if {$distance <= 10} {return 1}
return 0
}
```

A huge amount can be learned from reading other peopleâ€™s code. This is why we wanted to give exercism users the option of making their solutions public.

Here are some questions to help you reflect on this solution and learn the most from it.

- What compromises have been made?
- Are there new concepts here that you could read more about to improve your understanding?

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