diff --git a/2022/day11/common.bash b/2022/day11/common.bash
old mode 100755
new mode 100644
diff --git a/2022/day12/Makefile b/2022/day12/Makefile
new file mode 100644
index 0000000..e0add74
--- /dev/null
+++ b/2022/day12/Makefile
@@ -0,0 +1,111 @@
+# AOC daily Makefile - GNU make only.
+#
+# Copyright (C) 2021-2022 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/input.txt
+SHELL   := /bin/bash
+
+CC      := gcc
+BEAR    := bear
+CCLSFILE:= compile_commands.json
+
+LIB     := aoc_$(shell uname -m)
+INCDIR  := ../include
+LIBDIR  := ../lib
+LDFLAGS := -L$(LIBDIR)
+#LDLIB   := -l$(LIB) -lm
+LDLIB   := -l$(LIB)
+
+export LD_LIBRARY_PATH = $(LIBDIR)
+
+CFLAGS  += -std=gnu11
+CFLAGS  += -O2
+CFLAGS  += -g
+# for gprof
+# CFLAGS += -pg
+CFLAGS  += -Wall
+CFLAGS  += -Wextra
+CFLAGS  += -march=native
+# Next one may be useful for valgrind (some invalid instructions)
+# CFLAGS += -mno-tbm
+CFLAGS  += -Wmissing-declarations
+CFLAGS  += -Wno-unused-result
+
+CFLAGS  += -DDEBUG_DEBUG 	# activate general debug (debug.c)
+CFLAGS  += -DDEBUG_POOL		# memory pools management
+
+VALGRIND := valgrind
+VALGRINDFLAGS := --leak-check=full --show-leak-kinds=all --track-origins=yes \
+	--sigill-diagnostics=yes --quiet --show-error-list=yes
+
+
+TIME    := \time -f "\ttime: %E real, %U user, %S sys\n\tcontext-switch:\t%c+%w, page-faults: %F+%R\n"
+export PATH := .:$(PATH)
+
+.PHONY: clean all compile assembly memcheck memcheck1 memcheck2 part1 part2 ccls bear org
+
+all: README.org ccls part1 part2
+
+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 < $(INPUT)
+
+compile: aoc-c
+
+cpp: aoc-c.i
+
+assembly: aoc-c.s
+
+part1: aoc-c
+	@$(TIME) aoc.bash -p 1 < $(INPUT) 2>&1
+	@$(TIME) aoc-c -p 1 < $(INPUT)
+
+part2: aoc-c
+	@$(TIME) aoc.bash -p 2 < $(INPUT) 2>&1
+	@$(TIME) aoc-c -p 2 < $(INPUT)
+
+ccls: $(CCLSFILE)
+
+clean:
+	@rm -f aoc-c core* vgcore* gmon.out aoc-c.s aoc-c.i README.html compile_commands.json
+
+aoc-c: aoc-c.c common.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: README.org
+
+%.org: %.html
+	@echo generating $@. Cleanup before commit !
+	@pandoc $< -o $@
+
+# generate compile_commands.json
+$(CCLSFILE): aoc-c.c Makefile
+	$(BEAR) -- make clean compile
+
+bear: clean
+	@touch .ccls-root
+	@$(BEAR) -- make compile
diff --git a/2022/day12/README.org b/2022/day12/README.org
new file mode 100644
index 0000000..4dd4b76
--- /dev/null
+++ b/2022/day12/README.org
@@ -0,0 +1,100 @@
+** --- Day 12: Hill Climbing Algorithm ---
+You try contacting the Elves using your handheld device, but the river
+you're following must be too low to get a decent signal.
+
+You ask the device for a heightmap of the surrounding area (your puzzle
+input). The heightmap shows the local area from above broken into a
+grid; the elevation of each square of the grid is given by a single
+lowercase letter, where =a= is the lowest elevation, =b= is the
+next-lowest, and so on up to the highest elevation, =z=.
+
+Also included on the heightmap are marks for your current position (=S=)
+and the location that should get the best signal (=E=). Your current
+position (=S=) has elevation =a=, and the location that should get the
+best signal (=E=) has elevation =z=.
+
+You'd like to reach =E=, but to save energy, you should do it in /as few
+steps as possible/. During each step, you can move exactly one square
+up, down, left, or right. To avoid needing to get out your climbing
+gear, the elevation of the destination square can be /at most one
+higher/ than the elevation of your current square; that is, if your
+current elevation is =m=, you could step to elevation =n=, but not to
+elevation =o=. (This also means that the elevation of the destination
+square can be much lower than the elevation of your current square.)
+
+For example:
+
+#+begin_example
+Sabqponm
+abcryxxl
+accszExk
+acctuvwj
+abdefghi
+#+end_example
+
+Here, you start in the top-left corner; your goal is near the middle.
+You could start by moving down or right, but eventually you'll need to
+head toward the =e= at the bottom. From there, you can spiral around to
+the goal:
+
+#+begin_example
+v..v<<<<
+>v.vv<<^
+.>vv>E^^
+..v>>>^^
+..>>>>>^
+#+end_example
+
+In the above diagram, the symbols indicate whether the path exits each
+square moving up (=^=), down (=v=), left (=<=), or right (=>=). The
+location that should get the best signal is still =E=, and =.= marks
+unvisited squares.
+
+This path reaches the goal in =31= steps, the fewest possible.
+
+/What is the fewest steps required to move from your current position to
+the location that should get the best signal?/
+
+Your puzzle answer was =408=.
+
+** --- Part Two ---
+As you walk up the hill, you suspect that the Elves will want to turn
+this into a hiking trail. The beginning isn't very scenic, though;
+perhaps you can find a better starting point.
+
+To maximize exercise while hiking, the trail should start as low as
+possible: elevation =a=. The goal is still the square marked =E=.
+However, the trail should still be direct, taking the fewest steps to
+reach its goal. So, you'll need to find the shortest path from /any
+square at elevation =a=/ to the square marked =E=.
+
+Again consider the example from above:
+
+#+begin_example
+Sabqponm
+abcryxxl
+accszExk
+acctuvwj
+abdefghi
+#+end_example
+
+Now, there are six choices for starting position (five marked =a=, plus
+the square marked =S= that counts as being at elevation =a=). If you
+start at the bottom-left square, you can reach the goal most quickly:
+
+#+begin_example
+...v<<<<
+...vv<<^
+...v>E^^
+.>v>>>^^
+>^>>>>>^
+#+end_example
+
+This path reaches the goal in only =29= steps, the fewest possible.
+
+/What is the fewest steps required to move starting from any square with
+elevation =a= to the location that should get the best signal?/
+
+Your puzzle answer was =399=.
+
+Both parts of this puzzle are complete! They provide two gold stars: **
diff --git a/2022/day12/aoc.bash b/2022/day12/aoc.bash
new file mode 100755
index 0000000..2288d90
--- /dev/null
+++ b/2022/day12/aoc.bash
@@ -0,0 +1,200 @@
+#!/usr/bin/env bash
+#
+# aoc.bash: Advent of Code 2022, day 12
+#
+# Copyright (C) 2022 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>
+
+. common.bash
+
+#declare -a map map2
+declare -A height map visited
+declare -i X Y
+declare start end push=push1
+declare -a queue
+
+printmap() {
+    local -i x y
+    for (( y = 0; y < Y; ++y )); do
+        for (( x = 0; x < X; ++x )); do
+            printf "%2d " "${map["$x,$y"]}"
+        done
+        echo
+    done
+}
+
+printvis() {
+    local -i x y
+    for (( y = 0; y < Y; ++y )); do
+        for (( x = 0; x < X; ++x )); do
+            printf "%2d " "${visited["$x,$y"]}"
+        done
+        echo
+    done
+}
+
+push1() {                                         # push part 1
+    local -i _d="$1" _x="$2" _y="$3" _h="$4"
+    local _c="$_x,$_y"
+    printf "push d=%d x=%d y=%d h=%d nh=%d... " "$_d" "$_x" "$_y" "$_h" \
+           "${map[$_c]}"
+    if (( !visited[$_c] && map[$_c] <= (_h + 1) )); then
+        (( _d++ ))
+        visited["$_c"]=$_d
+        queue+=("$_d:$_c")
+        echo "$_d:$_c" pushed.
+    else
+        echo not pushed.
+    fi
+    #local str="$_d:$_x-$_y"
+    #queue+=("$1")
+}
+
+push2() {                                         # push part 2
+    local -i _d="$1" _x="$2" _y="$3" _h="$4"
+    local _c="$_x,$_y"
+    printf "push d=%d x=%d y=%d h=%d nh=%d... " "$_d" "$_x" "$_y" "$_h" \
+           "${map[$_c]}"
+    if (( !visited[$_c] && map[$_c] >= (_h - 1) )); then
+        (( _d++ ))
+        visited["$_c"]=$_d
+        queue+=("$_d:$_c")
+        echo "$_d:$_c" pushed.
+    else
+        echo not pushed.
+    fi
+    #local str="$_d:$_x-$_y"
+    #queue+=("$1")
+}
+
+pop() {
+    local -n _d="$1" _x="$2" _y="$3"
+    local head
+    ((!${#queue[@]})) && echo pop: queue empty. && return 1
+    head="${queue[0]}"
+    #echo "Q=${#queue[@]}=${queue[*]} head=$head"
+    # shellcheck disable=2034
+    printf "pop: %s\t" "$head"
+    _d=${head%:*}
+    # shellcheck disable=2034
+    head=${head#*:}
+    _x=${head%,*}
+    _y=${head#*,}
+    unset 'queue[0]'
+    queue=("${queue[@]}")
+    printf "pop: d=%d x=%d y=%d remain=%d\n"  "$_d" "$_x" "$_y" "${#queue[@]}"
+    #echo "Q=${#queue[@]}=${queue[*]} head=$head"
+    return 0
+}
+
+# initialize height values
+init() {
+    declare -i i=1
+    for c in {a..z}; do
+        (( height[$c] = i++ ))
+        #echo
+    done
+    height[S]=1
+    height[E]=26
+}
+
+parse() {
+    local -i part="$1"
+    local -a _map
+    local -i x y
+    local c
+    ((part == 2)) && push=push2
+
+    init
+    readarray -t _map
+    X=${#_map[0]}
+    Y=${#_map[@]}
+    echo "X=$X Y=$Y"
+    # create array map[x,y]
+    for (( y = 0; y < Y; ++y )); do
+        for (( x = 0; x < X; ++x )); do
+            c=${_map[$y]:x:1}
+            # printf "y=%d x=%d c=%s h=%d " "$y" "$x" "$c" "${height[$c]}"
+            map["$x,$y"]=${height[$c]}
+            # printf "M=%s\n" "${map["$x,$y"]}"
+            case "$c" in
+                S) start="$x,$y"
+                   ((part == 1)) && $push 0 "$x" "$y" 1
+                   #printf "\tstart\n"
+                   ;;
+                E) end="$x,$y"
+                   ((part == 2)) && $push 0 "$x" "$y" 1
+                   #printf "\tend\n"
+                   ;;
+            esac
+        done
+    done
+    printf "start=%s end=%s\n" "$start" "$end"
+    printmap
+}
+
+solve() {
+    #local depth coord
+    local -i h d x y
+
+
+    #push 0 ${start%-*} ${start#*-} 1
+    #push "11:46-55"
+    while pop d x y; do
+        (( h=${map["$x,$y"]} ))
+        if [[ $part == 1 ]]; then
+            if [[ "$x,$y" == "$end" ]]; then
+                res=$((d-1))
+                printmap
+                echo
+                printvis
+                return
+            fi
+        else
+            if [[ "${map["$x,$y"]}" == 1 ]]; then
+                res=$((d-1))
+                printmap
+                echo
+                printvis
+                return
+            fi
+        fi
+        if ((y > 0)); then                        # north
+            $push "$d" "$x" "$((y-1))" "$h"
+        fi
+        if ((x+1 < X)); then                      # east
+            $push "$d" "$((x+1))" "$y" "$h"
+        fi
+        if ((y+1 < Y)); then                      # south
+            $push "$d" "$x" "$((y+1))" "$h"
+        fi
+        if ((x > 0)); then                        # west
+            $push "$d" "$((x-1))" "$y" "$h"
+        fi
+        #echo "d=$d x=$x y=$y"
+        echo
+    done
+    #push "10:45-54"
+    # push "11:46-55"
+    # pop dep x y
+    # echo "d=$d x=$x y=$y"
+    # pop dep x y
+    # echo "d=$d x=$x y=$y"
+    # push "78:1-2"
+    # pop dep x y
+    # echo "d=$d x=$x y=$y"
+    # #pop d c
+    # #echo "d=$d c=$c"
+
+    # :
+    # #(( part == 2 )) && (( _loops = 10000, divisor = 1 ))
+}
+
+main "$@"
+exit 0
diff --git a/2022/day12/aoc.h b/2022/day12/aoc.h
new file mode 100644
index 0000000..2ef8361
--- /dev/null
+++ b/2022/day12/aoc.h
@@ -0,0 +1,17 @@
+/* aoc.c: Advent of Code 2022
+ *
+ * Copyright (C) 2022 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>
+ */
+#ifndef _AOC_H_
+#define _AOC_H_
+
+extern int parseargs(int ac, char**av);
+
+#endif  /* _AOC_H_ */
diff --git a/2022/day12/common.bash b/2022/day12/common.bash
new file mode 100644
index 0000000..5af1e54
--- /dev/null
+++ b/2022/day12/common.bash
@@ -0,0 +1,68 @@
+#!/usr/bin/env bash
+#
+# common.bash: Advent of Code 2022, common bash functions
+#
+# Copyright (C) 2022 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>
+
+# shellcheck disable=2034
+export cmdname=${0##*/}
+export debug=0
+export res
+export LANG=C
+
+shopt -s extglob
+set -o noglob
+
+usage() {
+    printf "usage: %s [-d DEBUG] [-p PART]\n" "$cmdname"
+    exit 1
+}
+
+checkargs() {
+    local part=1
+    while getopts p:d: todo; do
+        case "$todo" in
+            d)
+                if [[ "$OPTARG" =~ ^[[:digit:]+]$ ]]; then
+                    debug="$OPTARG"
+                else
+                    printf "%s: illegal [%s] debug level.\n" "$CMD" "$OPTARG"
+                    exit 1
+                fi
+                ;;
+            p)
+                if [[ "$OPTARG" =~ ^[12]$ ]]; then
+                    part="$OPTARG"
+                else
+                    printf "%s: illegal [%s] part.\n" "$CMD" "$OPTARG"
+                    exit 1
+                fi
+                ;;
+            *)
+                usage
+                ;;
+        esac
+    done
+    # Now check remaining argument (backup directory)
+    shift $((OPTIND - 1))
+
+    (( $# > 1 )) && usage
+    return "$part"
+}
+
+main() {
+    local -i part
+
+    checkargs "$@"
+    part=$?
+    parse "$part"
+    solve "$part"
+    printf "%s: res=%s\n" "$cmdname" "$res"
+}
diff --git a/2022/day12/common.c b/2022/day12/common.c
new file mode 100644
index 0000000..a3827b6
--- /dev/null
+++ b/2022/day12/common.c
@@ -0,0 +1,49 @@
+/* common.c: Advent of Code 2022, common functions
+ *
+ * Copyright (C) 2022 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>
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "aoc.h"
+#include "debug.h"
+
+static int usage(char *prg)
+{
+    fprintf(stderr, "Usage: %s [-d debug_level] [-p part] [-i input]\n", prg);
+    return 1;
+}
+
+int parseargs(int ac, char **av)
+{
+    int opt, part = 1;
+
+    while ((opt = getopt(ac, av, "d:p:")) != -1) {
+        switch (opt) {
+            case 'd':
+                debug_level_set(atoi(optarg));
+                break;
+            case 'p':                             /* 1 or 2 */
+                part = atoi(optarg);
+                if (part < 1 || part > 2)
+                    return usage(*av);
+                break;
+            case 'i':
+
+            default:
+                return usage(*av);
+        }
+    }
+    if (optind < ac)
+        return usage(*av);
+    return part;
+}
diff --git a/2022/day12/input/example.txt b/2022/day12/input/example.txt
new file mode 100644
index 0000000..86e9cac
--- /dev/null
+++ b/2022/day12/input/example.txt
@@ -0,0 +1,5 @@
+Sabqponm
+abcryxxl
+accszExk
+acctuvwj
+abdefghi
diff --git a/2022/day12/input/input.txt b/2022/day12/input/input.txt
new file mode 100644
index 0000000..bb083e9
--- /dev/null
+++ b/2022/day12/input/input.txt
@@ -0,0 +1,41 @@
+abaaaaaccccccccccccccccccaaaaaaaaaaaaaccccaaaaaaaccccccccccccccccccccccccccccaaaaaa
+abaaaaaaccaaaacccccccccccaaaaaaaaacaaaacaaaaaaaaaacccccccccccccccccccccccccccaaaaaa
+abaaaaaacaaaaaccccccccccaaaaaaaaaaaaaaacaaaaaaaaaacccccccccccccaacccccccccccccaaaaa
+abaaaaaacaaaaaacccccccccaaaaaaaaaaaaaaccaaacaaaccccccccccccccccaacccccccccccccccaaa
+abccaaaccaaaaaacccaaaaccaaaaaaaaaaaaaccccaacaaacccccccccaacaccccacccccccccccccccaaa
+abcccccccaaaaaccccaaaacccccaaaaacccaaaccaaaaaaccccccccccaaaaccccccccccccccccccccaac
+abcccccccccaaaccccaaaacccccaaaaacccccccccaaaaaccccccccccklllllccccccccccccccccccccc
+abcccccccccccccccccaaccccccccaaccccccccaaaaaaaccccccccckklllllllcccccddccccaacccccc
+abaccccccccccccccccccccccccccaaccccccccaaaaaaaaccccccckkkklslllllcccddddddaaacccccc
+abacccccccccccccccccccccccccccccccaaaccaaaaaaaaccccccckkkssssslllllcddddddddacccccc
+abaccccccccccccccccccccccccccccccccaaaaccaaacaccccccckkksssssssslllmmmmmdddddaacccc
+abcccccccccccccccaaacccccccccccccaaaaaaccaacccccccccckkkssssusssslmmmmmmmdddddacccc
+abcccccccaaccccaaaaacccccccccccccaaaaaccccccaaaaaccckkkrssuuuussssqmmmmmmmmdddccccc
+abcccccccaaccccaaaaaacccccccaaccccaaaaacccccaaaaacckkkkrruuuuuussqqqqqqmmmmdddccccc
+abccccaaaaaaaacaaaaaacccccccaaaaccaaccaccccaaaaaacjkkkrrruuuxuuusqqqqqqqmmmmeeccccc
+abcaaaaaaaaaaacaaaaaccccccaaaaaacccccaaccccaaaaajjjjrrrrruuuxxuvvvvvvvqqqmmmeeccccc
+abcaacccaaaaccccaaaaaaacccaaaaacccacaaaccccaaaajjjjrrrrruuuxxxxvvvvvvvqqqmmeeeccccc
+abaaaaccaaaaacccccccaaaccccaaaaacaaaaaaaacccaajjjjrrrrtuuuuxxxyvyyyvvvqqqnneeeccccc
+abaaaaaaaaaaacccaaaaaaaccccaacaacaaaaaaaacccccjjjrrrttttuxxxxxyyyyyvvvqqnnneeeccccc
+abaaaaaaaccaacccaaaaaaaaacccccccccaaaaaaccccccjjjrrrtttxxxxxxxyyyyyvvvqqnnneeeccccc
+SbaaaaaacccccccccaaaaaaaaaccccccccaaaaacccccccjjjrrrtttxxxEzzzzyyyvvrrrnnneeecccccc
+abaaaaacccccccccccaaaaaaacccccccccaaaaaaccccccjjjqqqtttxxxxxyyyyyvvvrrrnnneeecccccc
+abaaacccccccccccaaaaaaaccaaccccccccccaaccaaaaajjjqqqttttxxxxyyyyyyvvrrrnnneeecccccc
+abaaacccccccccccaaaaaaaccaaacaaacccccccccaaaaajjjjqqqtttttxxyywyyyywvrrnnnfeecccccc
+abcaaacccccccaaaaaaaaaaacaaaaaaaccccccccaaaaaaciiiiqqqqtttxwyywwyywwwrrrnnfffcccccc
+abcccccccccccaaaaaaaaaaccaaaaaacccccccccaaaaaacciiiiqqqqttwwywwwwwwwwrrrnnfffcccccc
+abccccccccccccaaaaaacccaaaaaaaacccccccccaaaaaaccciiiiqqqttwwwwwswwwwrrrrnnfffcccccc
+abccccccccccccaaaaaacccaaaaaaaaacccccccccaaacccccciiiqqqtswwwwssssrrrrrroofffcccccc
+abccccccaaaaacaaaaaacccaaaaaaaaaaccccccccccccccccciiiqqqssswsssssssrrrrooofffaccccc
+abccccccaaaaacaaccaaccccccaaacaaacccccccccccccccccciiiqqssssssspoorrrooooofffaacccc
+abcccccaaaaaacccccccccccccaaacccccccccccccccccccccciiiqppssssspppooooooooffffaacccc
+abcccccaaaaaacccccccccccccaacccccccccccccccccccccccciipppppppppppoooooooffffaaccccc
+abcccccaaaaaaccccccccccccccccccccccccccccccccccccccciihppppppppgggggggggfffaaaccccc
+abccccccaaacccccccccccccccccccccccaccccccccccccccccchhhhpppppphggggggggggfaaaaccccc
+abaaaccccccccccccccccccccccaccccaaacccccccccccccccccchhhhhhhhhhgggggggggcaacccccccc
+abaaccaaaccaccccccccccccccaaacccaaacaacccaaaaacccccccchhhhhhhhhgaaccccccccccccccccc
+abaaacaaacaacccccccccaaaccaaaacaaaaaaaaccaaaaaccccccccchhhhhhaaaaacccccccccccccccca
+abaaaccaaaaaccccccccccaaacaaaaaaaacaaaaccaaaaaaccccccccccaaacccaaaacccccccccccaccca
+abcccaaaaaaccccccccccaaaaaaaaaaaaacaaaaccaaaaaaccccccccccaaaccccaaaccccccccccaaaaaa
+abcccaaaaaaaacccccccaaaaaaaaaaaaaaaaaccccaaaaaacccccccccccccccccccccccccccccccaaaaa
+abcccaacaaaaaccccccaaaaaaaaaaaaaaaaaaacccccaacccccccccccccccccccccccccccccccccaaaaa
diff --git a/2022/include/pjwhash-inline.h b/2022/include/pjwhash-inline.h
index 75c2bcb..81dabb7 100644
--- a/2022/include/pjwhash-inline.h
+++ b/2022/include/pjwhash-inline.h
@@ -24,6 +24,16 @@
 #define _pjw_inline static inline
 #endif
 
+/**
+ * unsigned int pjwhash - PJW hash function
+ * @key:    the key address.
+ * @length: the length of key.
+ *
+ * This hash was created by Peter Jay Weinberger (AT&T Bell Labs):
+ * https://en.wikipedia.org/wiki/PJW_hash_function
+ *
+ * Return: the PJW hash.
+ */
 _pjw_inline unsigned int pjwhash(const void* key, uint length)
 {
    uint hash = 0, high;