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<span><a href="..">🏡</a></span>
<span><code>2020\day07.nim</code></span>
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<h2>Day 7: Handy Haversacks</h2>
<h3>General strategy</h3>
<p>The solution will be in 5 parts:</p>
<ol>
<li>colors: I will use global variables</li>
<li>parse a single rule: manual parsing (no regex, no npeg - tried but did not succeed at first try)</li>
<li>reversing the rules: while parsing the rules I will also create the mapping
from a color to its direct containers.</li>
<li>solve part 1: recursive</li>
<li>solve part 2: recursive</li>
</ol>
<h3>1. Colors</h3>
<p>I am going to use two global variables names and colors. Here are the functions needed for them.</p>
<p>I do not know why I set <code>Color = distinct int</code>, it is probably unnecessary and just complicates stuff.</p>
<pre><code class="nim hljs"><span class="hljs-keyword">type</span>
<span class="hljs-type">Color</span> = <span class="hljs-keyword">distinct</span> <span class="hljs-built_in">int</span> <span class="hljs-comment">## # why not use a distinct type to make our life a little bit messier?</span>
<span class="hljs-type">Names</span> = <span class="hljs-built_in">seq</span>[<span class="hljs-built_in">string</span>]
<span class="hljs-type">Colors</span> = <span class="hljs-type">OrderedTable</span>[<span class="hljs-built_in">string</span>, <span class="hljs-type">Color</span>]
<span class="hljs-keyword">var</span>
names: <span class="hljs-type">Names</span>
colors: <span class="hljs-type">Colors</span>
<span class="hljs-keyword">proc</span> addColor(name: <span class="hljs-built_in">string</span>) =
<span class="hljs-keyword">if</span> name <span class="hljs-keyword">not_in</span> names:
names.add name
<span class="hljs-keyword">let</span> i = names.len - <span class="hljs-number">1</span>
colors[name] = i.<span class="hljs-type">Color</span>
<span class="hljs-keyword">proc</span> `$`(c: <span class="hljs-type">Color</span>): <span class="hljs-built_in">string</span> =
names[c.<span class="hljs-built_in">int</span>] <span class="hljs-comment">## I take advantage that names is global</span>
<span class="hljs-keyword">proc</span> toColor(s: <span class="hljs-built_in">string</span>): <span class="hljs-type">Color</span> =
colors[s]
<span class="hljs-keyword">template</span> resetGlobals() =
<span class="hljs-comment">## to reset the globals (after solving for the example)</span>
names = @[]
colors = initOrderedTable[<span class="hljs-built_in">string</span>, <span class="hljs-type">Color</span>]()
addColor <span class="hljs-string">"shiny gold"</span> <span class="hljs-comment">## always will be the 0.Color</span>
resetGlobals
dump <span class="hljs-number">0.</span><span class="hljs-type">Color</span>
dump toColor(<span class="hljs-string">"shiny gold"</span>)
dump names
<span class="hljs-comment">## later on I will put Color in a table. You need this or you will get a rather cryptic error message</span>
<span class="hljs-keyword">proc</span> `==`(a, b: <span class="hljs-type">Color</span>): <span class="hljs-built_in">bool</span> {.borrow.}</code></pre>
<pre><samp>0.Color = shiny gold
toColor("shiny gold") = shiny gold
names = @["shiny gold"]</samp></pre>
<h3>What is a Rule and how to parse it</h3>
<p>note that parseRule does use the globals <code>names</code> and <code>colors</code>.</p>
<p>I did try first with npeg, but I am still missing stuff,
so for the moment I will keep to with manual parsing (<code>parseUntil</code> for the win!).</p>
<pre><code class="nim hljs"><span class="hljs-keyword">type</span>
<span class="hljs-type">Rule</span> = <span class="hljs-keyword">tuple</span>[col: <span class="hljs-type">Color</span>, cons: <span class="hljs-type">Contents</span>]
<span class="hljs-type">Contents</span> = <span class="hljs-built_in">seq</span>[<span class="hljs-keyword">tuple</span>[qty: <span class="hljs-built_in">int</span>, col: <span class="hljs-type">Color</span>]]
<span class="hljs-keyword">proc</span> parseRule(text: <span class="hljs-built_in">string</span>): <span class="hljs-type">Rule</span> =
<span class="hljs-keyword">var</span>
col: <span class="hljs-built_in">string</span>
cons: <span class="hljs-built_in">string</span>
qty: <span class="hljs-built_in">int</span>
<span class="hljs-keyword">let</span>
i = parseUntil(text, col, <span class="hljs-string">" bags"</span>)
j = <span class="hljs-string">" bags contain "</span>.len
<span class="hljs-keyword">discard</span> parseUntil(text, cons, <span class="hljs-string">"."</span>, start = i + j)
addColor col
<span class="hljs-literal">result</span>.col = col.toColor
<span class="hljs-keyword">for</span> con <span class="hljs-keyword">in</span> cons.split(<span class="hljs-string">", "</span>):
<span class="hljs-keyword">if</span> con == <span class="hljs-string">"no other bags"</span>:
<span class="hljs-keyword">break</span>
<span class="hljs-keyword">let</span> i = parseInt(con, qty)
<span class="hljs-keyword">discard</span> parseUntil(con, col, <span class="hljs-string">" bag"</span>, start = i + <span class="hljs-number">1</span>)
addColor col
<span class="hljs-literal">result</span>.cons.add (qty, col.toColor)
<span class="hljs-keyword">echo</span> parseRule <span class="hljs-string">"light red bags contain 1 bright white bag, 2 muted yellow bags."</span>
<span class="hljs-keyword">echo</span> parseRule <span class="hljs-string">"bright white bags contain 1 shiny gold bag."</span>
<span class="hljs-keyword">echo</span> parseRule <span class="hljs-string">"faded blue bags contain no other bags."</span>
<span class="hljs-keyword">echo</span> names
<span class="hljs-keyword">echo</span> colors</code></pre>
<pre><samp>(col: light red, cons: @[(qty: 1, col: bright white), (qty: 2, col: muted yellow)])
(col: bright white, cons: @[(qty: 1, col: shiny gold)])
(col: faded blue, cons: @[])
@["shiny gold", "light red", "bright white", "muted yellow", "faded blue"]
{"shiny gold": shiny gold, "light red": light red, "bright white": bright white, "muted yellow": muted yellow, "faded blue": faded blue}</samp></pre>
<h3>reversing the rules</h3>
<p>while parsing the rules I will also create the mapping
from a color to its direct containers.</p>
<p>I do not know why I create a <code>PuzzleInput</code> type but I like how it looks in proc signatures.</p>
<p>The parsing is finally applied to the example.</p>
<p>I will reuse the variables <code>rs</code> and <code>dc</code>.</p>
<pre><code class="nim hljs"><span class="hljs-keyword">type</span>
<span class="hljs-type">PuzzleInput</span> = <span class="hljs-built_in">string</span>
<span class="hljs-type">Rules</span> = <span class="hljs-type">OrderedTable</span>[<span class="hljs-type">Color</span>, <span class="hljs-type">Contents</span>]
<span class="hljs-type">DirContainers</span> = <span class="hljs-type">OrderedTable</span>[<span class="hljs-type">Color</span>, <span class="hljs-built_in">seq</span>[<span class="hljs-type">Color</span>]]
<span class="hljs-keyword">proc</span> parse(p: <span class="hljs-type">PuzzleInput</span>): (<span class="hljs-type">Rules</span>, <span class="hljs-type">DirContainers</span>) =
<span class="hljs-keyword">var</span>
r: <span class="hljs-type">Rule</span>
rs = initOrderedTable[<span class="hljs-type">Color</span>, <span class="hljs-type">Contents</span>]()
dc = initOrderedTable[<span class="hljs-type">Color</span>, <span class="hljs-built_in">seq</span>[<span class="hljs-type">Color</span>]]()
<span class="hljs-keyword">for</span> line <span class="hljs-keyword">in</span> p.splitLines:
r = parseRule line
rs[r.col] = r.cons
<span class="hljs-keyword">for</span> con <span class="hljs-keyword">in</span> r.cons:
<span class="hljs-keyword">if</span> con.col <span class="hljs-keyword">not_in</span> dc:
dc[con.col] = @[r.col]
<span class="hljs-keyword">elif</span> con.col <span class="hljs-keyword">not_in</span> dc[con.col]:
dc[con.col].add r.col
<span class="hljs-keyword">for</span> col <span class="hljs-keyword">in</span> colors.keys:
<span class="hljs-keyword">if</span> col.toColor <span class="hljs-keyword">not_in</span> dc:
dc[col.toColor] = newSeq[<span class="hljs-type">Color</span>]()
<span class="hljs-keyword">return</span> (rs, dc)
<span class="hljs-keyword">let</span> example = <span class="hljs-string">"""light red bags contain 1 bright white bag, 2 muted yellow bags.
dark orange bags contain 3 bright white bags, 4 muted yellow bags.
bright white bags contain 1 shiny gold bag.
muted yellow bags contain 2 shiny gold bags, 9 faded blue bags.
shiny gold bags contain 1 dark olive bag, 2 vibrant plum bags.
dark olive bags contain 3 faded blue bags, 4 dotted black bags.
vibrant plum bags contain 5 faded blue bags, 6 dotted black bags.
faded blue bags contain no other bags.
dotted black bags contain no other bags."""</span>.<span class="hljs-type">PuzzleInput</span>
<span class="hljs-keyword">var</span> (rs, dc) = parse example
<span class="hljs-keyword">echo</span> <span class="hljs-string">"Rules:"</span>
<span class="hljs-keyword">for</span> k, v <span class="hljs-keyword">in</span> rs:
<span class="hljs-keyword">echo</span> k, <span class="hljs-string">": "</span>, v
<span class="hljs-keyword">echo</span> <span class="hljs-string">"DirContainers:"</span>
<span class="hljs-keyword">for</span> k, v <span class="hljs-keyword">in</span> dc:
<span class="hljs-keyword">echo</span> k, <span class="hljs-string">": "</span>, v</code></pre>
<pre><samp>Rules:
light red: @[(qty: 1, col: bright white), (qty: 2, col: muted yellow)]
dark orange: @[(qty: 3, col: bright white), (qty: 4, col: muted yellow)]
bright white: @[(qty: 1, col: shiny gold)]
muted yellow: @[(qty: 2, col: shiny gold), (qty: 9, col: faded blue)]
shiny gold: @[(qty: 1, col: dark olive), (qty: 2, col: vibrant plum)]
dark olive: @[(qty: 3, col: faded blue), (qty: 4, col: dotted black)]
vibrant plum: @[(qty: 5, col: faded blue), (qty: 6, col: dotted black)]
faded blue: @[]
dotted black: @[]
DirContainers:
bright white: @[light red, dark orange]
muted yellow: @[light red, dark orange]
shiny gold: @[bright white, muted yellow]
faded blue: @[muted yellow, dark olive, vibrant plum]
dark olive: @[shiny gold]
vibrant plum: @[shiny gold]
dotted black: @[dark olive, vibrant plum]
light red: @[]
dark orange: @[]</samp></pre>
<h3>Solve part 1</h3>
<p>with a short and careful recursion (note I keep variable <code>ac</code> in each recursive call).</p>
<p>output for real input will come later (so that I reset once the globals)</p>
<pre><code class="nim hljs"><span class="hljs-keyword">type</span>
<span class="hljs-type">AllContainers</span> = <span class="hljs-type">OrderedSet</span>[<span class="hljs-type">Color</span>]
<span class="hljs-keyword">proc</span> allContainers(c: <span class="hljs-type">Color</span>; dc: <span class="hljs-type">DirContainers</span>; ac: <span class="hljs-keyword">var</span> <span class="hljs-type">AllContainers</span>) =
<span class="hljs-keyword">for</span> cx <span class="hljs-keyword">in</span> dc[c]:
<span class="hljs-keyword">if</span> cx <span class="hljs-keyword">in</span> ac:
ac.incl cx
<span class="hljs-keyword">else</span>:
ac.incl cx
allContainers(cx, dc, ac)
<span class="hljs-keyword">var</span> ac: <span class="hljs-type">AllContainers</span>
(<span class="hljs-number">0.</span><span class="hljs-type">Color</span>).allContainers(dc, ac)
<span class="hljs-keyword">echo</span> ac</code></pre>
<pre><samp>{bright white, light red, dark orange, muted yellow}</samp></pre>
<h3>Solve part2</h3>
<p>Showing first solving for the example.</p>
<p>I like the indentation trick I used to debug the solution, so I leave it visible.</p>
<pre><code class="nim hljs"><span class="hljs-keyword">var</span> ind = <span class="hljs-number">0</span>
<span class="hljs-keyword">proc</span> reqBags(c: <span class="hljs-type">Color</span>; rs: <span class="hljs-type">Rules</span>): <span class="hljs-built_in">int</span> =
ind += <span class="hljs-number">2</span>
<span class="hljs-comment">## echo ("color: " & $c).indent(ind)</span>
<span class="hljs-comment">## echo ("contents: " & $(rs[c])).indent(ind)</span>
<span class="hljs-keyword">for</span> con <span class="hljs-keyword">in</span> rs[c]:
<span class="hljs-literal">result</span> += con.qty
<span class="hljs-literal">result</span> += con.qty * (reqBags(con.col, rs))
<span class="hljs-comment">## echo ("result: " & $result).indent(ind)</span>
ind -= <span class="hljs-number">2</span>
<span class="hljs-keyword">echo</span> <span class="hljs-string">"reqBags(example): "</span>, (<span class="hljs-number">0.</span><span class="hljs-type">Color</span>).reqBags(rs)</code></pre>
<pre><samp>reqBags(example): 32</samp></pre>
<h3>Getting the stars</h3>
<p>Solutions for my puzzle input</p>
<pre><code class="nim hljs"><span class="hljs-keyword">let</span> input = <span class="hljs-string">"2020/input07.txt"</span>.readFile.<span class="hljs-type">PuzzleInput</span>
resetGlobals
ac = initOrderedSet[<span class="hljs-type">Color</span>]() <span class="hljs-comment">## I need to reset this one too.</span>
(rs, dc) = parse input
(<span class="hljs-number">0.</span><span class="hljs-type">Color</span>).allContainers(dc, ac)
<span class="hljs-keyword">echo</span> <span class="hljs-string">"part1: "</span>, ac.len
<span class="hljs-keyword">echo</span> <span class="hljs-string">"part2: "</span>, (<span class="hljs-number">0.</span><span class="hljs-type">Color</span>).reqBags(rs)</code></pre>
<pre><samp>part1: 124
part2: 34862</samp></pre>
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<pre><code class="nim hljs"><span class="hljs-keyword">import</span> nimib, animu, sugar
nbInit
nbText: <span class="hljs-string">"## Day 7: Handy Haversacks"</span>
<span class="hljs-comment"># I should recover in nimib the simple toc example, it is indeed useful.</span>
nbText: <span class="hljs-string">"""### General strategy
The solution will be in 5 parts:
1. colors: I will use global variables
2. parse a single rule: manual parsing (no regex, no npeg - tried but did not succeed at first try)
3. reversing the rules: while parsing the rules I will also create the mapping
from a color to its direct containers.
4. solve part 1: recursive
5. solve part 2: recursive
"""</span>
nbText: <span class="hljs-string">"""### 1. Colors
I am going to use two global variables names and colors. Here are the functions needed for them.
I do not know why I set `Color = distinct int`, it is probably unnecessary and just complicates stuff.
"""</span>
nbCode:
<span class="hljs-keyword">type</span>
<span class="hljs-type">Color</span> = <span class="hljs-keyword">distinct</span> <span class="hljs-built_in">int</span> <span class="hljs-comment">### why not use a distinct type to make our life a little bit messier?</span>
<span class="hljs-type">Names</span> = <span class="hljs-built_in">seq</span>[<span class="hljs-built_in">string</span>]
<span class="hljs-type">Colors</span> = <span class="hljs-type">OrderedTable</span>[<span class="hljs-built_in">string</span>, <span class="hljs-type">Color</span>]
<span class="hljs-keyword">var</span>
names: <span class="hljs-type">Names</span>
colors: <span class="hljs-type">Colors</span>
<span class="hljs-keyword">proc</span> addColor(name: <span class="hljs-built_in">string</span>) =
<span class="hljs-keyword">if</span> name <span class="hljs-keyword">not_in</span> names:
names.add name
<span class="hljs-keyword">let</span> i = names.len - <span class="hljs-number">1</span>
colors[name] = i.<span class="hljs-type">Color</span>
<span class="hljs-keyword">proc</span> `$`(c: <span class="hljs-type">Color</span>): <span class="hljs-built_in">string</span> = names[c.<span class="hljs-built_in">int</span>] <span class="hljs-comment">## I take advantage that names is global</span>
<span class="hljs-keyword">proc</span> toColor(s: <span class="hljs-built_in">string</span>): <span class="hljs-type">Color</span> = colors[s]
<span class="hljs-keyword">template</span> resetGlobals =
<span class="hljs-comment">## to reset the globals (after solving for the example)</span>
names = @[]
colors = initOrderedTable[<span class="hljs-built_in">string</span>, <span class="hljs-type">Color</span>]()
addColor <span class="hljs-string">"shiny gold"</span> <span class="hljs-comment">## always will be the 0.Color</span>
resetGlobals
dump <span class="hljs-number">0.</span><span class="hljs-type">Color</span>
dump toColor(<span class="hljs-string">"shiny gold"</span>)
dump names
<span class="hljs-comment">## later on I will put Color in a table. You need this or you will get a rather cryptic error message</span>
<span class="hljs-keyword">proc</span> `==`(a,b: <span class="hljs-type">Color</span>): <span class="hljs-built_in">bool</span> {.borrow.}
nbText: <span class="hljs-string">"""### What is a Rule and how to parse it
note that parseRule does use the globals `names` and `colors`.
I did try first with npeg, but I am still missing stuff,
so for the moment I will keep to with manual parsing (`parseUntil` for the win!)."""</span>
nbCode:
<span class="hljs-keyword">type</span>
<span class="hljs-type">Rule</span> = <span class="hljs-keyword">tuple</span>[col: <span class="hljs-type">Color</span>, cons: <span class="hljs-type">Contents</span>]
<span class="hljs-type">Contents</span> = <span class="hljs-built_in">seq</span>[<span class="hljs-keyword">tuple</span>[qty: <span class="hljs-built_in">int</span>, col: <span class="hljs-type">Color</span>]]
<span class="hljs-keyword">proc</span> parseRule(text: <span class="hljs-built_in">string</span>): <span class="hljs-type">Rule</span> =
<span class="hljs-keyword">var</span>
col: <span class="hljs-built_in">string</span>
cons: <span class="hljs-built_in">string</span>
qty: <span class="hljs-built_in">int</span>
<span class="hljs-keyword">let</span>
i = parseUntil(text, col, <span class="hljs-string">" bags"</span>)
j = <span class="hljs-string">" bags contain "</span>.len
<span class="hljs-keyword">discard</span> parseUntil(text, cons, <span class="hljs-string">"."</span>, start=i+j)
addColor col
<span class="hljs-literal">result</span>.col = col.toColor
<span class="hljs-keyword">for</span> con <span class="hljs-keyword">in</span> cons.split(<span class="hljs-string">", "</span>):
<span class="hljs-keyword">if</span> con == <span class="hljs-string">"no other bags"</span>:
<span class="hljs-keyword">break</span>
<span class="hljs-keyword">let</span>
i = parseInt(con, qty)
<span class="hljs-keyword">discard</span> parseUntil(con, col, <span class="hljs-string">" bag"</span>, start=i+<span class="hljs-number">1</span>)
addColor col
<span class="hljs-literal">result</span>.cons.add (qty, col.toColor)
<span class="hljs-keyword">echo</span> parseRule <span class="hljs-string">"light red bags contain 1 bright white bag, 2 muted yellow bags."</span>
<span class="hljs-keyword">echo</span> parseRule <span class="hljs-string">"bright white bags contain 1 shiny gold bag."</span>
<span class="hljs-keyword">echo</span> parseRule <span class="hljs-string">"faded blue bags contain no other bags."</span>
<span class="hljs-keyword">echo</span> names
<span class="hljs-keyword">echo</span> colors
nbText: <span class="hljs-string">"""### reversing the rules
while parsing the rules I will also create the mapping
from a color to its direct containers.
I do not know why I create a `PuzzleInput` type but I like how it looks in proc signatures.
The parsing is finally applied to the example.
I will reuse the variables `rs` and `dc`."""</span>
nbCode:
<span class="hljs-keyword">type</span>
<span class="hljs-type">PuzzleInput</span> = <span class="hljs-built_in">string</span>
<span class="hljs-type">Rules</span> = <span class="hljs-type">OrderedTable</span>[<span class="hljs-type">Color</span>, <span class="hljs-type">Contents</span>]
<span class="hljs-type">DirContainers</span> = <span class="hljs-type">OrderedTable</span>[<span class="hljs-type">Color</span>, <span class="hljs-built_in">seq</span>[<span class="hljs-type">Color</span>]]
<span class="hljs-keyword">proc</span> parse(p: <span class="hljs-type">PuzzleInput</span>): (<span class="hljs-type">Rules</span>, <span class="hljs-type">DirContainers</span>) =
<span class="hljs-keyword">var</span>
r: <span class="hljs-type">Rule</span>
rs = initOrderedTable[<span class="hljs-type">Color</span>, <span class="hljs-type">Contents</span>]()
dc = initOrderedTable[<span class="hljs-type">Color</span>, <span class="hljs-built_in">seq</span>[<span class="hljs-type">Color</span>]]()
<span class="hljs-keyword">for</span> line <span class="hljs-keyword">in</span> p.splitLines:
r = parseRule line
rs[r.col] = r.cons
<span class="hljs-keyword">for</span> con <span class="hljs-keyword">in</span> r.cons:
<span class="hljs-keyword">if</span> con.col <span class="hljs-keyword">not_in</span> dc:
dc[con.col] = @[r.col]
<span class="hljs-keyword">elif</span> con.col <span class="hljs-keyword">not_in</span> dc[con.col]:
dc[con.col].add r.col
<span class="hljs-keyword">for</span> col <span class="hljs-keyword">in</span> colors.keys:
<span class="hljs-keyword">if</span> col.toColor <span class="hljs-keyword">not_in</span> dc:
dc[col.toColor] = newSeq[<span class="hljs-type">Color</span>]()
<span class="hljs-keyword">return</span> (rs, dc)
<span class="hljs-keyword">let</span> example = <span class="hljs-string">"""light red bags contain 1 bright white bag, 2 muted yellow bags.
dark orange bags contain 3 bright white bags, 4 muted yellow bags.
bright white bags contain 1 shiny gold bag.
muted yellow bags contain 2 shiny gold bags, 9 faded blue bags.
shiny gold bags contain 1 dark olive bag, 2 vibrant plum bags.
dark olive bags contain 3 faded blue bags, 4 dotted black bags.
vibrant plum bags contain 5 faded blue bags, 6 dotted black bags.
faded blue bags contain no other bags.
dotted black bags contain no other bags."""</span>.<span class="hljs-type">PuzzleInput</span>
<span class="hljs-keyword">var</span>
(rs, dc) = parse example
<span class="hljs-keyword">echo</span> <span class="hljs-string">"Rules:"</span>
<span class="hljs-keyword">for</span> k, v <span class="hljs-keyword">in</span> rs:
<span class="hljs-keyword">echo</span> k, <span class="hljs-string">": "</span>, v
<span class="hljs-keyword">echo</span> <span class="hljs-string">"DirContainers:"</span>
<span class="hljs-keyword">for</span> k, v <span class="hljs-keyword">in</span> dc:
<span class="hljs-keyword">echo</span> k, <span class="hljs-string">": "</span>, v
nbText: <span class="hljs-string">"""### Solve part 1
with a short and careful recursion (note I keep variable `ac` in each recursive call).
output for real input will come later (so that I reset once the globals)"""</span>
nbCode:
<span class="hljs-keyword">type</span> <span class="hljs-type">AllContainers</span> = <span class="hljs-type">OrderedSet</span>[<span class="hljs-type">Color</span>]
<span class="hljs-keyword">proc</span> allContainers(c: <span class="hljs-type">Color</span>, dc: <span class="hljs-type">DirContainers</span>, ac: <span class="hljs-keyword">var</span> <span class="hljs-type">AllContainers</span>) =
<span class="hljs-keyword">for</span> cx <span class="hljs-keyword">in</span> dc[c]:
<span class="hljs-keyword">if</span> cx <span class="hljs-keyword">in</span> ac: <span class="hljs-comment">## not sure if I need this, but for sure it is a protection against infinite recursion</span>
ac.incl cx
<span class="hljs-keyword">else</span>:
ac.incl cx
allContainers(cx, dc, ac)
<span class="hljs-keyword">var</span> ac: <span class="hljs-type">AllContainers</span>
(<span class="hljs-number">0.</span><span class="hljs-type">Color</span>).allContainers(dc, ac)
<span class="hljs-keyword">echo</span> ac
nbText: <span class="hljs-string">"""### Solve part2
Showing first solving for the example.
I like the indentation trick I used to debug the solution, so I leave it visible."""</span>
nbCode:
<span class="hljs-keyword">var</span> ind = <span class="hljs-number">0</span>
<span class="hljs-keyword">proc</span> reqBags(c: <span class="hljs-type">Color</span>, rs: <span class="hljs-type">Rules</span>): <span class="hljs-built_in">int</span> =
ind += <span class="hljs-number">2</span>
<span class="hljs-comment">##echo ("color: " & $c).indent(ind)</span>
<span class="hljs-comment">##echo ("contents: " & $(rs[c])).indent(ind)</span>
<span class="hljs-keyword">for</span> con <span class="hljs-keyword">in</span> rs[c]:
<span class="hljs-literal">result</span> += con.qty
<span class="hljs-literal">result</span> += con.qty*(reqBags(con.col, rs))
<span class="hljs-comment">##echo ("result: " & $result).indent(ind)</span>
ind -= <span class="hljs-number">2</span>
<span class="hljs-keyword">echo</span> <span class="hljs-string">"reqBags(example): "</span>, (<span class="hljs-number">0.</span><span class="hljs-type">Color</span>).reqBags(rs)
nbText: <span class="hljs-string">"### Getting the stars</span><span class="hljs-meta">\n</span><span class="hljs-string">Solutions for my puzzle input"</span>
nbCode:
<span class="hljs-keyword">let</span> input = <span class="hljs-string">"2020/input07.txt"</span>.readFile.<span class="hljs-type">PuzzleInput</span>
resetGlobals
ac = initOrderedSet[<span class="hljs-type">Color</span>]() <span class="hljs-comment">## I need to reset this one too.</span>
(rs, dc) = parse input
(<span class="hljs-number">0.</span><span class="hljs-type">Color</span>).allContainers(dc, ac)
<span class="hljs-keyword">echo</span> <span class="hljs-string">"part1: "</span>, ac.len
<span class="hljs-keyword">echo</span> <span class="hljs-string">"part2: "</span>, (<span class="hljs-number">0.</span><span class="hljs-type">Color</span>).reqBags(rs)
<span class="hljs-comment">#gotTheStar</span>
<span class="hljs-comment">#gotTheStar</span>
nbSave</code></pre>
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