2022 day 6 init + bash part 1

2022/day06/Makefile

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+# 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

2022/day06/README.org

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+** --- Day 6: Tuning Trouble ---
+The preparations are finally complete; you and the Elves leave camp on
+foot and begin to make your way toward the /star/ fruit grove.
+
+As you move through the dense undergrowth, one of the Elves gives you a
+handheld /device/. He says that it has many fancy features, but the most
+important one to set up right now is the /communication system/.
+
+However, because he's heard you have [[/2016/day/6][significant]]
+[[/2016/day/25][experience]] [[/2019/day/7][dealing]]
+[[/2019/day/9][with]] [[/2019/day/16][signal-based]]
+[[/2021/day/25][systems]], he convinced the other Elves that it would be
+okay to give you their one malfunctioning device - surely you'll have no
+problem fixing it.
+
+As if inspired by comedic timing, the device emits a few colorful
+sparks.
+
+To be able to communicate with the Elves, the device needs to /lock on
+to their signal/. The signal is a series of seemingly-random characters
+that the device receives one at a time.
+
+To fix the communication system, you need to add a subroutine to the
+device that detects a /start-of-packet marker/ in the datastream. In the
+protocol being used by the Elves, the start of a packet is indicated by
+a sequence of /four characters that are all different/.
+
+The device will send your subroutine a datastream buffer (your puzzle
+input); your subroutine needs to identify the first position where the
+four most recently received characters were all different. Specifically,
+it needs to report the number of characters from the beginning of the
+buffer to the end of the first such four-character marker.
+
+For example, suppose you receive the following datastream buffer:
+
+#+begin_example
+mjqjpqmgbljsphdztnvjfqwrcgsmlb
+#+end_example
+
+After the first three characters (=mjq=) have been received, there
+haven't been enough characters received yet to find the marker. The
+first time a marker could occur is after the fourth character is
+received, making the most recent four characters =mjqj=. Because =j= is
+repeated, this isn't a marker.
+
+The first time a marker appears is after the /seventh/ character
+arrives. Once it does, the last four characters received are =jpqm=,
+which are all different. In this case, your subroutine should report the
+value =7=, because the first start-of-packet marker is complete after 7
+characters have been processed.
+
+Here are a few more examples:
+
+- =bvwbjplbgvbhsrlpgdmjqwftvncz=: first marker after character =5=
+- =nppdvjthqldpwncqszvftbrmjlhg=: first marker after character =6=
+- =nznrnfrfntjfmvfwmzdfjlvtqnbhcprsg=: first marker after character =10=
+- =zcfzfwzzqfrljwzlrfnpqdbhtmscgvjw=: first marker after character =11=
+
+/How many characters need to be processed before the first
+start-of-packet marker is detected?/
+
+Your puzzle answer was =1658=.
+
+The first half of this puzzle is complete! It provides one gold star: *
+
+** --- Part Two ---
+Your device's communication system is correctly detecting packets, but
+still isn't working. It looks like it also needs to look for /messages/.
+
+A /start-of-message marker/ is just like a start-of-packet marker,
+except it consists of /14 distinct characters/ rather than 4.
+
+Here are the first positions of start-of-message markers for all of the
+above examples:
+
+- =mjqjpqmgbljsphdztnvjfqwrcgsmlb=: first marker after character =19=
+- =bvwbjplbgvbhsrlpgdmjqwftvncz=: first marker after character =23=
+- =nppdvjthqldpwncqszvftbrmjlhg=: first marker after character =23=
+- =nznrnfrfntjfmvfwmzdfjlvtqnbhcprsg=: first marker after character =29=
+- =zcfzfwzzqfrljwzlrfnpqdbhtmscgvjw=: first marker after character =26=
+
+/How many characters need to be processed before the first
+start-of-message marker is detected?/
+
+Answer:
+
+Although it hasn't changed, you can still [[file:6/input][get your
+puzzle input]].
+
+You can also [Shareon
+[[https://twitter.com/intent/tweet?text=I%27ve+completed+Part+One+of+%22Tuning+Trouble%22+%2D+Day+6+%2D+Advent+of+Code+2022&url=https%3A%2F%2Fadventofcode%2Ecom%2F2022%2Fday%2F6&related=ericwastl&hashtags=AdventOfCode][Twitter]]
+[[javascript:void(0);][Mastodon]]] this puzzle.

2022/day06/aoc.bash

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+#!/usr/bin/env bash
+#
+# aoc.bash: Advent of Code 2022, day 6
+#
+# 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 stacks=() rules=()
+
+parse() {
+    local -i _queue _state=1
+    local _input
+    local -a _parse
+    local cur=""
+    local -i lcur=0 i
+
+    read -r _input
+    len=${#_input}
+
+    lcur=0
+    for (( i = 0; i < len - 4; ++i )); do
+        echo
+        nextc=${_input:i:1}                       # get next char
+        printf "next=%s cur=%s lcur=%d\n" "$nextc" "$cur" "$lcur"
+        for ((j = 0; j < lcur; ++j)); do          # compare with previous ones
+            printf "compare %s with %d:%s\n" "$nextc" "$j" "${cur:j:1}"
+            if [[ $nextc == "${cur:j:1}" ]]; then
+                cur=${cur:j+1}$nextc
+                (( lcur = lcur - (j + 1) + 1))
+                printf "\t-> equal cur=%d:%s" "$lcur" "$cur"
+                continue 2
+            fi
+        done
+        cur+=$nextc
+        ((lcur++))
+        ((lcur == 4)) && break
+    done
+    echo "$cur" $((i + 1))
+}
+
+solve() {
+    local -i _part="$1" _i=0 _j=0 _nb _from _to
+    local -a _rule
+
+    for ((; _i < ${#rules[@]}; ++_i )); do
+        read -ra _rule <<< "${rules[$_i]}"
+        (( _nb = _rule[0], _from = _rule[1] - 1, _to = _rule[2] - 1 ))
+        if ((_part == 1)); then
+            # move elements one by one
+            for ((_j = 0; _j < _nb; ++_j)); do
+                stacks[$_to]="${stacks[$_from]:0:1}${stacks[$_to]}"
+                stacks[$_from]=${stacks[$_from]:1}
+            done
+        else
+            # move elements by block
+            stacks[$_to]="${stacks[$_from]:0:_nb}${stacks[$_to]}"
+            stacks[$_from]=${stacks[$_from]:_nb}
+        fi
+    done
+    printf -v res "%c" "${stacks[@]}"
+}
+
+main "$@"
+exit 0

2022/day06/aoc.h

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+/* 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_ */

2022/day06/common.bash

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+#!/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"
+}

2022/day06/common.c

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+/* 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;
+}

2022/day06/input/example.txt

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+mjqjpqmgbljsphdztnvjfqwrcgsmlb

2022/day06/input/example2.txt

@@ -0,0 +1 @@
+bvwbjplbgvbhsrlpgdmjqwftvncz

2022/day06/input/example3.txt

@@ -0,0 +1 @@
+nppdvjthqldpwncqszvftbrmjlhg

2022/day06/input/example4.txt

@@ -0,0 +1 @@
+nznrnfrfntjfmvfwmzdfjlvtqnbhcprsg

2022/day06/input/example5.txt

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+zcfzfwzzqfrljwzlrfnpqdbhtmscgvjw

2022/day06/input/input.txt

@@ -0,0 +1 @@
+cbhbmmqnmmqvqfqgqcqmmtvvvdsvscvssmfmhfmhhgdgcclhlnnvmnvmnnwngnqggqlqhhbqbfbvffcpfcfpcpmcppsgssvcvmmdwmwsmwswnwvnvvtgvgfgqqnlltgllpplhpllrnrwrtrzrlrzllpnlpnplnlwnnzfztzcchczctcbbpwpbbfhhqllgrllnnghnnlnznzzlqqmggqbgbjjlnlnjllwlnwnjnbjnnhhcddgmdmqmllfjllddmgmpggtvvqqwmmhcmmjpjdpdqqnhhqbhhscstsvttbwtwdtwwjffvccrwrvvnqqtwwhgwhwthwthhvshsfsjstshthqqdfdhdqhqrqggfffvhffhbbwtbtvtwvvwgvvjjjvtjvvlmlmtmztmthmhttjwwmqqjffhvhqvvrddbsbfbgffmcfffqqfzzgmggzvggbjjmccftcftfnttqqjzjdzdrrgvgsgvvlqvlqqlplnnjccjqcjcgjgfjgjlgjjzhhjbbbfdbfddgccncppsbbjjsttcqtqgqpqllqggtsthhtvvtrttbthtnhhddvnnbggmtggcsgcscmmvmllttjbjggbzbttrfttgsstwtftdthdththbttcggdldtdlttbvvpgpjpwpwvwcwjwsjsttznztzftzzjpzzrtzrztrrtsrrdtrdtdbdhhdgdwwnjnnvjvsjjrwjjvrrzvrvllrgghgbbgbsssslqlrllbjbttzfztzpzzvtvccszsddtqttjllqgqgpqphptpwttwtmtltljjfnnzwzmzlzssghssqhhphbhfftwwqmwmzzqtzqzqrrndrrmrqrzrszzrcrbccglgcgwgrgdggtvtpptgtfgflglgrrnvrvhrrhlrhhfchfhdhzzwggvbbgfgrrpdrdccfllqflfmlfmlmbbhnbbsblbzbgbqqjppcddcvvsddjfjjlnnwbbflfzzmlmddjssjffcqffwdfdqqphpnhppbttjfjzzdvdjvvddnfffmjfmfmpfmmmdlmlrrhqqcpcmclmmbmppzczjjmlltqlqzzqgqcggdmdzznnnnsjjvbjjwbwhbhfhvvtmmsfmmcgmcmwcwhwnhhpccmbmdbmbgbjbggqqccfllfqqmqwwzbblffthhdnncqnccqppldlpldpllzmmsqqdffnggqlqtllwlglnlnhlhflfssvzzrllbtbnbgnnfvfllwslszswsnnpwwppvspsmmnfnpffrmrhmmctttrjrbjrjpjtpjpssdwdtwtmmtgtsgttlwttfrfvvpjpcjccmtthhldhllzslshhnrnvvfddnllltclcrrhnnjwwwpfpddmtmsmfflslrlmlmwmllgfgmfgmmjttpcpspslsjspsqstqsqqpsprphrrpqqfzqqwcwcddsjjpvvfnfvnnnrncnwcwczzcwzwnwmwffbdfbdfdjjhrhvhhvwvsvhshnhwwzlwlnnphhtjjmljjqzjjsjgsjshhwjjmttvgvsgstggrcrmmrqrhrqrzrmzmggqvqtqgtqqqqltqqwggmmzggjccgmgwgqqmnqnrnprptrrvfrvffnmnfmmnnnwzzldlvlgvlvqqpnphpgglhlshlhzzpcptpssblqvdbpbbcrngctqgptccwpdcpbcjwdmcrzmhwffgzqmmqwpqvplwzmjlzmvmzmbtqjnhzrpppnpntvmjbzmvhjvbgflmmjnwssvqvbnbddfcwqdtvpvddctmpptcjmvwszhbsttcbjlfjvwlljhlqlvvsnzphdjhfswltdhzprltzcszrgcmnmfznmbccstjvjngwpbsfqssfwvpdhhmlmzttzlszsgpvvbcfvzrlsttlqpnqhwtbqfjnbztnwfnhlhfltgdtsrrwrfhlssvsgzpffnnrhgcvclqnjgfhhzswllvcjffpngcmtjphwnbdfrrgjfrfqbnvbwgccsjvvmjgcvqvtggnvgvgnnchbblqnvvdgjtvdmfrzvhvhzcbqzdslphjjqtcwjqptstvvpqgdbgbcmmchjpvjhvbwtlmlnqpldfcbmwvrmpqcsfdhmmwnbvmpglcfbnsgjmljcwpzpwffcqfrbdrztzhqzhzpcrjfdmrctttdrzlmzcqwjftngwjmgqscftnpbjwqrcvqwbwbdhbhvrdcvgrvctjgwjtmdgzwgvdbmsrjpsbhwcqlqzjnzmgpctlwqhfnbmgsprjcqtfjjvzljqpfqgnvrgnjjlmpqgnzpmpsvzjmtvnfgslldjtjdwlzrvqrbvcpspzpcdnpdjmhcdhsbmthmgjqchqwwsnfjnwgpctlwcdpqpmzqcrptscngqnmhzwjdcqwvdmlzntsfbstbtmmnlsspjbjjdspnslgcnlbfnbhjlzjhrrmdbbwtswqpbpwtzhcnldbsfrvndzvcgzjprcrclhfwbvzgthcglfzqrshgtvbflvnznhmlzdtfnrsltnnppqgrtndbsfqmftdnzmqfwdpcrmssldmrrnzchnqpflgbqzqjjrzlfnptqdwzdhmctfbztmfcmbqcwjmgnwgqzqjctphrrthgvpvppztvpzgzhdszfhlzlcnwmfrlsnvftfrlfvbnlwzctphhpfvszntqcvnfmvmwwhsjlnpfhcpjvrncgmsbprwwllvnsbjfhtbtmcvvpzcvqrrqdvgzvllvcvnvvbftngqcqcvvbsqfshmnhwptcsbsnjzltqzmflftrhblqszrzsbfcpgzncvwhlqlcbmgjdpfcmlgdfphsfcgqccthmlzjbdwpsbddwwrtwmsvqwbzwhzmghhrspvbptznqsqvhgnhlwqjnhgnzprrtjddwtqfsshjrvlglhdlstghftmllvzmmfglnscnrtgcwwwzjphzhvqlctdwjlqvbsvlgzrdpvjhhcthgjhlwsgfzlschhfprfcrzfrzmnlwvqsnqlllczwfhswchrlggqszwrvpldrffnzrffbhtfbslgcdrqpjcrbqsrgfrhttcptncfndcbsdbjsqjvgbmnmhlnbltdcgbmllpgjmgljvglrwmrvgthhhzrsmzvgwcfgvcsbzpjcqnhrzhznzjcjghhwqvllrmsvlpzlssrdsqwvzvqwsvfsjqvbgrfbmfzlchqsjgncbljtvzsfdnvmfzcbrlnnvvmjbmgjmqzjtdzpljdwqtvwsrlbslwfvlgbtnmlpcwmngncnmdhqctshmjmnhpqcqzhvlbvgptctrvggdgnpnrlnngrfhsqdfthvcnpwjfjnslcqlfrfvhnctmsqgnqmgpwtlzhtdqhqqrcllzjccnszsqvrzhcffvnfnstgdmljdrqrndljdnfbbjvmpqdnqhtdlnzcvnfjlvzmfzrndhtglvngmbrdbpbnhvfmrbcwqzttnjplgrhchjtfjwfbjfbmzlrnllhzccpfhfhnjpfvzlpbqnhwmpssvwtzhdbtnbtllhpfdcqjjnzgbdrfjjbcltnzdrmtmsmvpjtmdnqszgbqncsvhjbgwswhmghpvstrqbglgrtgbchttbznvvdhppzwnttpgcbdjdhlsqhhtlphjjrjncrmfdtjhdwmjgmpngnbptzwgwdztmhtpglnftwpnnmrmcwfhwnhlsbwsrjnlmdlmffbzsnhsvnbldwtrrhdhfsjdrsnzlgtfzcwwqrfhtrmjhmphqndwtbpczvmfgczmdlqjqdlwmvjjzwmqnpvwzmtjwtprlnbvjdhpjgndrwzcfthnwhnhqpwtcjlhrhdplzsncfmszmhjmgljhnlsrrfwplclcvjjqmtpnwbtsbwdnjdlqntvdnfgwbpwspssprbffjdlcvbwcqlttnwnhwdspfsjhppbhspnrvrsfmzvbwwtjfzmnzwgqddbmcjzzqhqlgrglsvgsjdwlnsbtmqgsnfwwqrjsbcgdlmbgqwvgpqllqwbcplfjrgnzsdtdtvqnrbcrqjhdtqqplvszvtlflgbpwnpzczbvhzfjrslcwcswsgfvvsswzzwhtfjfpsrvcfnrs