Two bullet roulette: Difference between revisions

 

The following is supposedly a question given to mathematics graduates seeking jobs on Wall Street:

A revolver handgun has a revolving cylinder with six chambers for bullets.

It is loaded with the following procedure:

1. Check the first chamber to the right of the trigger for a bullet. If a bullet

is seen, the cylinder is rotated one chamber clockwise and the next chamber

checked until an empty chamber is found.

2. A cartridge containing a bullet is placed in the empty chamber.

3. The cylinder is then rotated one chamber clockwise.

A. Spinning the cylinder after loading the first bullet, and spinning again after the first shot.

B. Spinning the cylinder after loading the first bullet only.

C. Spinning the cylinder after firing the first shot only.

D. Not spinning the cylinder either after loading the first bullet or after the first shot.

E. The probability is the same for all cases.

 

;Task:

# Run a repeated simulation of each of the above scenario, calculating the percentage of suicide with a randomization of the four spinning, loading and firing order scenarios.

Youtube video on the Russian 1895 Nagant revolver [[https://www.youtube.com/watch?v=Dh1mojMaEtM]]

<br><br>

 

=={{header|C}}==

{{trans|Go}}

#include <stdio.h>

#include <stdlib.h>

 

return 0;

{{out}}

<pre>load, spin, load, spin, fire, spin, fire produces 55.456% deaths.

load, load, spin, fire, spin, fire produces 55.487% deaths.

load, load, spin, fire, fire produces 50.289% deaths.</pre>

 

=={{header|Factor}}==

{{trans|Julia}}

{{trans|Python}}

math random sequences ;

IN: rosetta-code.roulette

} [ run-test ] assoc-each ;

 

{{out}}

<pre>"rosetta-code.roulette" run</pre>

Method <load, load, spin, fire, fire> produces 49.841% deaths.

</pre>

 

=={{header|Go}}==

{{trans|Wren}}

Though procedural rather than OO.

 

import (

fmt.Printf("%-40s produces %6.3f%% deaths.\n", mstring(m), pc)

}

 

{{out}}

load, load, spin, fire, spin, fire produces 55.405% deaths.

load, load, spin, fire, fire produces 49.889% deaths.

</pre>

 

=={{header|Julia}}==

{{trans|Python}}

 

function load()

 

testmethods()

<pre>

Method load, spin, load, spin, fire, spin, fire produces 55.54253 per cent deaths.

=={{header|Kotlin}}==

{{trans|C}}

 

val cylinder = Array(6) { false }

test("LLSFSF");

test("LLSFF");

{{out}}

<pre>load, spin, load, spin, fire, spin, fire produces 55.638% deaths.

load, load, spin, fire, spin, fire produces 55.725% deaths.

load, load, spin, fire, fire produces 49.875% deaths.</pre>

 

=={{header|Perl}}==

{{trans|Raku}}

use warnings;

use feature 'say';

$total += &$ref for 1..$trials;

printf "%7s %.2f%%\n", $ref, $total / $trials * 100;

{{out}}

<pre>LSLSFSF 55.04%

 

=={{header|Phix}}==

{{out}}

<pre>

Load/Spin/Fire method percentage fatalities:

</pre>

 

=={{header|Python}}==

import numpy as np

 

percentage = 100 * sum([method() for _ in range(TESTCOUNT)]) / TESTCOUNT

print("Method", name, "produces", percentage, "per cent deaths.")

<pre>

Method load, spin, load, spin, fire, spin, fire produces 55.652 per cent deaths.

=={{header|Raku}}==

 

 

my @cyl;

 

say "{.fmt('%7s')}: %{(%revolver{$_} / $trials × 100).fmt('%.2f')}"

{{out|Sample output (default; 6 shooter)}}

<pre>LSLSFSF: %55.37

 

Changing the cartridge chamber from an index array to a simple string made the program around &nbsp; '''200%''' &nbsp; faster.

parse arg cyls tests seed . /*obtain optional arguments from the CL*/

if cyls=='' | cyls=="," then cyls= 6 /*Not specified? Then use the default.*/

if tests=='' | tests=="," then tests= 100000 /* " " " " " " */

if datatype(seed, 'W') then call random ,,seed /* " " " " " " */

#= words(scenarios) /*the number of actions in a scenario. */

/*The scenarios are case insensitive. */

exit 0 /*stick a fork in it, we're all done. */

/*──────────────────────────────────────────────────────────────────────────────────────*/

spin: ?= random(1, cyls); if ?\==cyls then @= substr(@ || @, ? + 1, cyls); return

/*──────────────────────────────────────────────────────────────────────────────────────*/

/*──────────────────────────────────────────────────────────────────────────────────────*/

{{out|output|text=&nbsp; when using the default inputs, &nbsp; showing that 2^nd option &nbsp; '''B''' &nbsp; has the highest probability for a suicide:}}

<pre>

</pre>

 

=={{header|Wren}}==

{{libheader|Wren-fmt}}

 

var Rand = Random.new()

for (t in 1..tests) sum = sum + rev.method(m)

Fmt.print("$-40s produces $6.3f\% deaths.", Revolver.mstring(m), sum * 100 / tests)

 

{{out}}