day 11

Makefile

@@ -98,6 +98,16 @@ day10part2:
 	@echo
 	./build/day10part2
 
+day11part1:
+	fpc src/day11/part1.pas -obuild/day11part1
+	@echo
+	./build/day11part1
+
+day11part2:
+	fpc src/day11/part2.pas -obuild/day11part2
+	@echo
+	./build/day11part2
+
 
 clean:
 	rm build/*

resources/day11.txt

@@ -0,0 +1,140 @@
+.....#...............#......................................................................#.............................#..........#......
+........................................#............................#......#...............................................................
+..............................#..............#....................................#..............................................#..........
+..............#........................................................................#....................................................
+..#...........................................................................................#.............................................
+..................#.....................................#.....#......................................#.........#.......#....................
+...........#......................................#.....................#...........#................................................#......
+.............................#............................................................#.....................................#...........
+.....#..................#.................#.........................#......................................#................................
+....................................#.................#........................#..........................................................#.
+................#..............................#....................................................#.......................................
+..............................................................#.........................#.......................#.....................#.....
+............#...............#......................#.....................#..............................#...................................
+......................................#...............................................................................#.....................
+.........................................................#..................................................................................
+..............................................#.............................................................................................
+..#.................#.....................................................................#.....#..........#..............#......#..........
+..............................................................................#.............................................................
+..........................................#.........................#..............................................#........................
+.....#........#.............#...........................#...........................................#.......................................
+..................................#...............#.............#.................#..........................#.....................#........
+.......................................................................#....................................................................
+...............................................................................................................................#.........#..
+#.......................................#....................................................#.........................#....................
+........#...............#....................................#...........................................#..................................
+...............................#............................................................................................................
+.........................................................#..................................................................................
+..#..........................................#........................................#.............#............................#..........
+......................#............................#.................#........#.............................................................
+.........#.......#...........................................................................#.....................#.........#.........#....
+................................#............................................................................#..............................
+.........................................................................................#..................................................
+.#.........................................#.........#..........#.......................................................#...................
+....................#.................#...............................................................#.....................................
+............................................................................#...............................................................
+........................#.........................................................................................#.................#.......
+.............#.......................................................#......................................................#...............
+.......#.................................#.....#..............................................................#.............................
+#...............................#...............................................................#.....................#.....................
+.....................................#...................#.......................#.....#.......................................#............
+..........................#.................#......#...................................................................................#....
+..............#.............................................................................................................................
+...#..........................................................................#............................................#................
+.............................................................................................#.....................#......................#.
+.......................................#..........................................................................................#.........
+.......................................................................................................#....................................
+.....#.........#.................#.................#............#.........................#.................#...............................
+............................#.....................................................#.........................................................
+...........................................#................................................................................................
+....................................#.......................#.........................#............................#.....#..................
+............................................................................................................................................
+.....................#..................#................................#......#.....................................................#.....
+.......................................................#.........#...............................#.....#....................................
+............#.................................................................................................................#.............
+..............................................#..............#.......#.................................................#....................
+................................................................................................................#...........................
+.........#.............................................................................#............#.......................................
+.............................#...........................................#.....#............................................................
+.....#..........#.....#...........#.............#.....#.............................................................................#.......
+...........................................#............................................................#.....#.............................
+......................................#.........................#.........................#.....................................#...........
+............................................................................................................................................
+.......#.....#.....#........................................#.................................#.............................................
+.........................................#................................................................#.....#......#....................
+........................#.......#..................#.................................#.......................................#.......#......
+..............................................#.............................................................................................
+...............................................................................#............................................................
+......................................................#..........#..........................................................................
+...#......#.................#.............#.............................#..........................#...............................#........
+.............................................................#........................#..........................#.........#................
+......................................#....................................................#.............................................#..
+............................................................................................................................................
+...............#......#.......................#.....#.......................................................#...............................
+.#......#.......................#.........................#.......#....................................#....................................
+...............................................................................................#........................#......#.......#....
+............#...............#............#....................#........#..........#.........................................................
+...............................................................................................................#............................
+..........................................................................................................#.................#...............
+......................#........#.........................................................................................................#..
+....................................................................................#.....#.....#....................#......................
+.#.........#...............#........................................#...............................................................#.......
+..................#......................................................#..........................#.......................................
+.................................#.............#................................................................#.......#...................
+........................#......................................................#..............#................................#............
+.....#..........................................................#.....#.................#..................................................#
+.....................................#......#.........#...............................................#.....................................
+............................................................................................................................................
+............................................................................................................................................
+.................................#..........................................#................#...................#..............#...........
+.......#....................#............#.............................................#...................................#................
+..#................#........................................#.......#..............................#........................................
+........................#...........................................................................................................#.......
+...........#..........................................#.........................#......................#....................................
+...........................................#................................................................................................
+......#...............................................................................#.........#...........................................
+............................#.....................#................#........................................#...........#...................
+..................#.........................................#...............................................................................
+........................#...............#................................#.......#..............................#............#..............
+............#......................#.................#..................................................#..................................#
+..#................................................................................................#........................................
+.........................................................................................................................#..................
+..................................................................#................................................#................#.......
+.......#.....................................#..............................................................................................
+.................#...............#......#.....................#.............................................................................
+....................................................................................#..................................#....................
+..............................................................................................#............#................................
+....#......................#................................................................................................................
+......................................................#.................................#..........................#.............#..........
+..........#.................................................................................................................#...............
+.................................#..........#..................................#............................................................
+.......................................................................................................................................#....
+.......................................#..................................................................#......#..........................
+.............................#.........................................................#.......#............................................
+.........#....................................#............#.................................................................#..............
+...#...............................................................................#.................#......................................
+..................................................................................................................................#.........
+....................#.............#...................................................................................#....................#
+....................................................#...........#...........#...............................................................
+.........................................................................................................#..................................
+..........#...............................#............................#....................................................................
+.............................................................#....................#.............................#..............#............
+.#...............#..........................................................................#..........................................#....
+............................#...............................................................................................................
+............#......................................#............#..................................................................#........
+.......#...............................................................................................................#....................
+..................................#.......#..........................#........#...............#..........#....................#.............
+....................#....................................#............................#..........................#.......................#..
+..............................................................#.............................................................................
+..#............................#............................................................................#...............................
+..............#.....................#...............................................................................................#.......
+..........................#........................................#....................................#...........#.......................
+..........................................#.................................#.................#.............................................
+................................................#...........#..........#.....................................................#..............
+.........#..................................................................................................................................
+...................................................................................#............................#.......#...................
+....#.............................#.............................#.......................................................................#...
+.........................................#.........................................................#........................................
+....................#...........................................................................................................#...........
+..............#........................................#..................................#...................#......................#......
+.........#.................#........................................#...........#........................................#..................

resources/day11sample.txt

@@ -0,0 +1,10 @@
+...#......
+.......#..
+#.........
+..........
+......#...
+.#........
+.........#
+..........
+.......#..
+#...#.....

src/day11/part1.pas

@@ -0,0 +1,113 @@
+program day11part1;
+uses sysutils;
+
+
+function dist_between(x1, x2: int32; empty_list: array of boolean): int32;
+var
+    i: int32;
+begin
+    
+    { swap operands so x1 is always smaller}
+    if (x2 < x1) then
+    begin
+        i := x2;
+        x2 := x1;
+        x1 := i;
+    end;
+
+    { calculate distance }
+    dist_between := 0;
+    for i := x1 to x2 - 1 do
+    begin
+
+        dist_between := dist_between + 1;
+
+        { if gap, increment by an additional 1 }
+        if empty_list[i] then
+            dist_between := dist_between + 1;
+        
+
+    end;
+end;
+
+function galaxy_dist(g1, g2: array of int64; row_list, col_list: array of boolean): int32;
+begin
+    galaxy_dist := dist_between(g1[0], g2[0], col_list) + dist_between(g1[1], g2[1], row_list);
+end;
+
+var
+    file_: text;
+
+    str: string;
+
+    galaxies: array[0..1000, 0..1] of int64;
+    galaxy_count: int32;
+
+    column_empty: array[1..1000] of boolean;
+    row_empty: array[1..1000] of boolean;
+
+    i, j: int32;
+    count: int32;
+
+    sum: int32;
+
+begin
+     { open inp.txt for reading }
+    assign(file_, 'resources/day11.txt');
+    reset(file_);
+
+    { set row/cols to empty }
+    for i := 0 to 1000 do
+    begin
+        column_empty[i] := true;
+        row_empty[i] := true;
+    end;
+
+    count := 0;
+    galaxy_count := 0;
+
+    { read file }
+    while not EOF(file_) do
+    begin
+
+        count := count + 1;
+
+        readln(file_, str);
+
+        for i := 1 to length(str) do
+        begin
+            
+            if str[i] = '#' then
+            begin
+
+                { record this galaxy }
+                galaxy_count := galaxy_count + 1;
+
+                galaxies[galaxy_count][0] := i;
+                galaxies[galaxy_count][1] := count;
+
+                { mark rows/cols as nonempty }
+                row_empty[count] := false;
+                column_empty[i] := false;
+
+            end;
+
+        end;
+    end;
+
+    sum := 0;
+    { for each pair }
+    for i := 1 to galaxy_count do
+    begin
+        for j := i + 1 to galaxy_count do
+        begin
+
+        { sum the pairwise distance }
+        sum := sum + galaxy_dist(galaxies[i], galaxies[j], row_empty, column_empty);
+
+        end;
+    end;
+
+    writeln('The sum is ', sum);
+end.
+

src/day11/part2.pas

@@ -0,0 +1,113 @@
+program day11part1;
+uses sysutils;
+
+
+function dist_between(x1, x2: int32; empty_list: array of boolean): int64;
+var
+    i: int32;
+begin
+    
+    { swap operands so x1 is always smaller}
+    if (x2 < x1) then
+    begin
+        i := x2;
+        x2 := x1;
+        x1 := i;
+    end;
+
+    { calculate distance }
+    dist_between := 0;
+    for i := x1 to x2 - 1 do
+    begin
+
+        dist_between := dist_between + 1;
+
+        { if gap, increment by an additional 999999 }
+        if empty_list[i] then
+            dist_between := dist_between + 999999;
+        
+
+    end;
+end;
+
+function galaxy_dist(g1, g2: array of int64; row_list, col_list: array of boolean): int64;
+begin
+    galaxy_dist := dist_between(g1[0], g2[0], col_list) + dist_between(g1[1], g2[1], row_list);
+end;
+
+var
+    file_: text;
+
+    str: string;
+
+    galaxies: array[0..1000, 0..1] of int64;
+    galaxy_count: int32;
+
+    column_empty: array[1..1000] of boolean;
+    row_empty: array[1..1000] of boolean;
+
+    i, j: int32;
+    count: int32;
+
+    sum: int64;
+
+begin
+     { open inp.txt for reading }
+    assign(file_, 'resources/day11.txt');
+    reset(file_);
+
+    { set row/cols to empty }
+    for i := 0 to 1000 do
+    begin
+        column_empty[i] := true;
+        row_empty[i] := true;
+    end;
+
+    count := 0;
+    galaxy_count := 0;
+
+    { read file }
+    while not EOF(file_) do
+    begin
+
+        count := count + 1;
+
+        readln(file_, str);
+
+        for i := 1 to length(str) do
+        begin
+            
+            if str[i] = '#' then
+            begin
+
+                { record this galaxy }
+                galaxy_count := galaxy_count + 1;
+
+                galaxies[galaxy_count][0] := i;
+                galaxies[galaxy_count][1] := count;
+
+                { mark rows/cols as nonempty }
+                row_empty[count] := false;
+                column_empty[i] := false;
+
+            end;
+
+        end;
+    end;
+
+    sum := 0;
+    { for each pair }
+    for i := 1 to galaxy_count do
+    begin
+        for j := i + 1 to galaxy_count do
+        begin
+
+        { sum the pairwise distance }
+        sum := sum + galaxy_dist(galaxies[i], galaxies[j], row_empty, column_empty);
+
+        end;
+    end;
+
+    writeln('The sum is ', sum);
+end.
+