day 15

Makefile

@@ -144,5 +144,15 @@ day14part2:
 	@echo
 	./build/day14part2
 
+day15part1:
+	fpc src/day15/part1.pas -obuild/day15part1
+	@echo
+	./build/day15part1
+
+day15part2:
+	fpc src/day15/part2.pas -obuild/day15part2
+	@echo
+	./build/day15part2
+
 clean:
 	rm build/*

resources/day15sample.txt

@@ -0,0 +1 @@
+rn=1,cm-,qp=3,cm=2,qp-,pc=4,ot=9,ab=5,pc-,pc=6,ot=7

src/day15/part1.pas

@@ -0,0 +1,85 @@
+{$mode objfpc}
+
+program day12part1;
+uses sysutils;
+
+type
+    stringarray = array of string;
+
+function split_to_str(s: AnsiString; delim: char): stringarray;
+var
+    i, last_delim, count : int32;
+    c: char;
+begin
+
+    { there will always be at least one number }
+    count := 1;
+    { count number of delimeters }
+    for c in s do
+    begin
+        if c = delim then
+            count := count + 1;
+    end;
+
+    { allocate enough space for count}
+    setlength(split_to_str, count);
+
+    count := 0;
+    last_delim := 0;
+
+    { second interation }
+    for i := 1 to length(s) do
+    begin
+        { if this is a delimeter }
+        if s[i] = delim then
+        begin
+            { add the value between this delimiter and the previous one to splitted }
+            split_to_str[count] := copy(s, last_delim + 1, i - last_delim - 1);
+            count := count + 1;
+            last_delim := i;
+        end;
+    end;
+    
+    { don't forget the final value }
+    split_to_str[count] := copy(s, last_delim + 1, length(s) - last_delim)
+end;
+
+function hash(s: string): int32;
+var
+    c: char;
+begin
+    hash := 0;
+    for c in s do
+        hash := ((hash + ord(c)) * 17) and 255;
+
+
+end;
+
+var
+
+    s: AnsiString;
+    to_hash: array of string;
+
+    split: array of string;
+
+    file_: text;
+
+    sum: int32;
+
+begin
+
+    assign(file_, 'resources/day15.txt');
+    reset(file_);
+    readln(file_, s);
+
+    to_hash := split_to_str(s, ',');
+    writeln(length(to_hash));
+
+    sum := 0;
+
+    for s in to_hash do
+        sum := sum + hash(s);
+
+    writeln('The sum is ', sum);
+end.
+

src/day15/part2.pas

@@ -0,0 +1,194 @@
+{$mode objfpc}
+
+program day12part1;
+uses sysutils;
+
+type
+    stringarray = array of string;
+    lens = record
+        label_: string;
+        focal: int32;
+    end;
+
+
+function split_to_str(s: AnsiString; delim: char): stringarray;
+var
+    i, last_delim, count : int32;
+    c: char;
+begin
+
+    { there will always be at least one number }
+    count := 1;
+    { count number of delimeters }
+    for c in s do
+    begin
+        if c = delim then
+            count := count + 1;
+    end;
+
+    { allocate enough space for count}
+    setlength(split_to_str, count);
+
+    count := 0;
+    last_delim := 0;
+
+    { second interation }
+    for i := 1 to length(s) do
+    begin
+        { if this is a delimeter }
+        if s[i] = delim then
+        begin
+            { add the value between this delimiter and the previous one to splitted }
+            split_to_str[count] := copy(s, last_delim + 1, i - last_delim - 1);
+            count := count + 1;
+            last_delim := i;
+        end;
+    end;
+    
+    { don't forget the final value }
+    split_to_str[count] := copy(s, last_delim + 1, length(s) - last_delim)
+end;
+
+function streq(s1: string; s2: string): boolean;
+var
+    i: int32;
+begin
+    streq := true;
+    for i := 1 to length(s1) do
+    begin
+        if (s1[i] <> s2[i]) then
+        begin
+            streq := false;
+            break;
+        end;
+    end;
+end;
+
+function hash(s: string): int32;
+var
+    c: char;
+begin
+    hash := 0;
+    for c in s do
+        hash := ((hash + ord(c)) * 17) and 255;
+
+
+end;
+
+var
+    { ideally a linked list would be nice for the second dim, but eh.}
+    boxes: array[0..255, 1..100] of lens;
+    b_length: array[0..255] of int32;
+
+procedure insert_lens(l: string; f: int32);
+var
+    hvalue: int32;
+    i: int32;
+begin
+
+    hvalue := hash(l);
+
+    { check for duplicate }
+    for i := 1 to b_length[hvalue] do
+    begin
+        if streq(boxes[hvalue, i].label_, l) then
+        begin
+            boxes[hvalue, i].focal := f;
+            exit;
+        end;
+    end;
+
+    { add to end }
+
+    b_length[hvalue] := b_length[hvalue] + 1;
+    boxes[hvalue, b_length[hvalue]].label_ := l;
+    boxes[hvalue, b_length[hvalue]].focal := f;
+
+end;
+
+procedure remove_lens(l: string);
+var
+    hvalue: int32;
+    i: int32;
+    shifting: boolean;
+begin
+    hvalue := hash(l);
+    
+    shifting := false;
+    for i := 1 to b_length[hvalue] do
+    begin
+        if shifting then
+            boxes[hvalue, i - 1] := boxes[hvalue, i]
+        else if streq(boxes[hvalue, i].label_, l) then
+            shifting := true;
+    end;
+
+    if shifting then
+        b_length[hvalue] := b_length[hvalue] - 1;
+end;
+
+procedure write_boxes();
+var
+    i, j: int32;
+begin
+
+    for i := 0 to 255 do
+    begin
+        if b_length[i] <> 0 then
+        begin
+
+            write('Box ', i, ': ');
+
+            for j := 1 to b_length[i] do
+            begin
+                write('[', boxes[i, j].label_, ' ', boxes[i, j].focal, '] ');
+            end;
+
+            writeln();
+        end;
+    end;
+end;
+
+var
+
+    s: AnsiString;
+    to_hash: array of string;
+
+    split: array of string;
+
+    file_: text;
+
+    i, j: int32;
+    sum: int32;
+
+begin
+
+    assign(file_, 'resources/day15.txt');
+    reset(file_);
+    readln(file_, s);
+
+    to_hash := split_to_str(s, ',');
+
+    { fill boxes }
+    for s in to_hash do
+    begin
+        if s[length(s)] = '-' then
+            remove_lens(copy(s, 0, length(s) - 1))
+        else if s[length(s) - 1] = '=' then
+        begin
+            val(s[length(s)], i);
+            insert_lens(copy(s, 0, length(s) - 2), i);
+        end;
+    end;
+
+    { sum }
+    sum := 0;
+    for i := 0 to 255 do
+        for j := 1 to b_length[i] do
+            sum := sum + (i + 1) * j * boxes[i, j].focal;
+
+
+    write_boxes();
+    writeln('The sum is ', sum);
+end.
+