2019 day 6 init

2019/day06/EXAMPLE.txt

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+COM)B
+B)C
+C)D
+D)E
+E)F
+B)G
+G)H
+D)I
+E)J
+J)K
+K)L

2019/day06/Makefile

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+# AOC daily Makefile - GNU make only.
+#
+# Copyright (C) 2021 Bruno Raoult ("br")
+# Licensed under the GNU General Public License v3.0 or later.
+# Some rights reserved. See COPYING.
+#
+# You should have received a copy of the GNU General Public License along with this
+# program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+#
+# SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+#
+
+INPUT   := INPUT.txt
+SHELL   := /bin/bash
+
+CC      := gcc
+
+LIB     := aoc_$(shell uname -m)
+INCDIR  := ../include
+LIBDIR  := ../lib
+LDFLAGS := -L$(LIBDIR)
+#LDLIB   := -l$(LIB) -lm
+LDLIB   := -l$(LIB)
+
+export LD_LIBRARY_PATH = $(LIBDIR)
+
+CFLAGS  += -std=gnu99
+CFLAGS  += -O2
+CFLAGS  += -g
+# for gprof
+#CFLAGS += -pg
+CFLAGS  += -Wall
+CFLAGS  += -Wextra
+CFLAGS  += -march=native
+# Next one may be useful for valgrind (some invalid instructions)
+# CFLAGS += -mno-tbm
+CFLAGS  += -Wmissing-declarations
+CFLAGS  += -Wno-unused-result
+
+CFLAGS  += -DDEBUG_DEBUG 	# activate general debug (debug.c)
+CFLAGS  += -DDEBUG_POOL		# memory pools management
+
+VALGRIND := valgrind
+VALGRINDFLAGS := --leak-check=full --show-leak-kinds=all --track-origins=yes \
+	--sigill-diagnostics=yes --quiet --show-error-list=yes
+
+
+TIME    := \time -f "\ttime: %E real, %U user, %S sys\n\tcontext-switch:\t%c+%w, page-faults: %F+%R\n"
+export PATH := .:$(PATH)
+
+.PHONY: clean all compile assembly memcheck memcheck1 memcheck2 ex1 ex2
+
+all: README.org ex1 ex2
+
+memcheck: memcheck1 memcheck2
+
+memcheck1: aoc-c
+	@$(VALGRIND) $(VALGRINDFLAGS) aoc-c -p 1 < $(INPUT)
+
+memcheck2: aoc-c
+	@$(VALGRIND) $(VALGRINDFLAGS) aoc-c -p 2 < $(INPUT)
+	@#@valgrind -s --track-origins=yes aoc-c -p 2 < $(INPUT)
+
+compile: aoc-c
+
+assembly: aoc-c.s
+
+ex1: aoc-c
+	@$(TIME) aoc-c -p 1 < $(INPUT)
+
+ex2: aoc-c
+	@$(TIME) aoc-c -p 2 < $(INPUT)
+
+clean:
+	@rm -f aoc-c core* vgcore* gmon.out aoc-c.s aoc-c.i README.html
+
+.c:
+	@echo compiling $<
+	@$(CC) $(CFLAGS) $(LDFLAGS) -I $(INCDIR) $< $(LDLIB) -o $@
+
+# generate pre-processed file (.i) and assembler (.s)
+%.i: %.c
+	@echo generating $@
+	@$(CC) -E $(CFLAGS) -I $(INCDIR) $< -o $@
+
+%.s: %.c
+	@echo generating $@
+	@$(CC) -S -fverbose-asm $(CFLAGS) -I $(INCDIR) $< -o $@
+
+# generate README.org from README.html (must cleanup !)
+%.org: %.html
+	@echo generating $@. Cleanup before commit !
+	@pandoc $< -o $@

2019/day06/README.org

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+** --- Day 6: Universal Orbit Map ---
+You've landed at the Universal Orbit Map facility on Mercury. Because
+navigation in space often involves transferring between orbits, the
+orbit maps here are useful for finding efficient routes between, for
+example, you and Santa. You download a map of the local orbits (your
+puzzle input).
+
+Except for the universal Center of Mass (=COM=), every object in space
+is in orbit around exactly one other object. An
+[[https://en.wikipedia.org/wiki/Orbit][orbit]] looks roughly like this:
+
+#+BEGIN_EXAMPLE
+                    \
+                     \
+                      |
+                      |
+  AAA--> o            o <--BBB
+                      |
+                      |
+                     /
+                    /
+#+END_EXAMPLE
+
+In this diagram, the object =BBB= is in orbit around =AAA=. The path
+that =BBB= takes around =AAA= (drawn with lines) is only partly shown.
+In the map data, this orbital relationship is written =AAA)BBB=, which
+means "=BBB= is in orbit around =AAA=".
+
+Before you use your map data to plot a course, you need to make sure it
+wasn't corrupted during the download. To verify maps, the Universal
+Orbit Map facility uses /orbit count checksums/ - the total number of
+/direct orbits/ (like the one shown above) and /indirect orbits/.
+
+Whenever =A= orbits =B= and =B= orbits =C=, then =A= /indirectly orbits/
+=C=. This chain can be any number of objects long: if =A= orbits =B=,
+=B= orbits =C=, and =C= orbits =D=, then =A= indirectly orbits =D=.
+
+For example, suppose you have the following map:
+
+#+BEGIN_EXAMPLE
+  COM)B
+  B)C
+  C)D
+  D)E
+  E)F
+  B)G
+  G)H
+  D)I
+  E)J
+  J)K
+  K)L
+#+END_EXAMPLE
+
+Visually, the above map of orbits looks like this:
+
+#+BEGIN_EXAMPLE
+          G - H       J - K - L
+         /           /
+  COM - B - C - D - E - F
+                 \
+                  I
+#+END_EXAMPLE
+
+In this visual representation, when two objects are connected by a line,
+the one on the right directly orbits the one on the left.
+
+Here, we can count the total number of orbits as follows:
+
+- =D= directly orbits =C= and indirectly orbits =B= and =COM=, a total
+  of =3= orbits.
+- =L= directly orbits =K= and indirectly orbits =J=, =E=, =D=, =C=, =B=,
+  and =COM=, a total of =7= orbits.
+- =COM= orbits nothing.
+
+The total number of direct and indirect orbits in this example is =42=.
+
+/What is the total number of direct and indirect orbits/ in your map
+data?