rename repo, subdir for yearly challenges

2020/day11/ex2.bash

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+#!/bin/bash
+#
+# ex2.bash: Advent2020 game, day 11/game 2.
+
+CMD=${0##*/}
+shopt -s extglob
+
+declare -a rowsstr rows seats control
+declare -i NCOLS NROWS SIZE
+declare zeroed
+
+function print_control() {
+	local -i r c
+	for ((r=0; r<NROWS; ++r)); do
+		for ((c=0; c<NCOLS; ++c)); do
+			printf "%2d " "${control[r*NCOLS+c]}" >&2
+		done
+		echo >&2
+	done
+	echo >&2
+}
+function print_seats() {
+	local -i r c
+	for ((r=0; r<NROWS; ++r)); do
+		for ((c=0; c<NCOLS; ++c)); do
+			printf "%d " "${seats[r*NCOLS+c]}" >&2
+		done
+		echo >&2
+	done
+	echo >&2
+}
+function run() {
+	local -i c r i cell changed=1
+	#local -a control
+	local -i loop=0 seated=0
+
+	read -ra seats <<< "${rows[*]}"
+	#print_seats
+	while ((changed > 0)); do
+		changed=0
+		seated=0
+		read -ra control <<< "$zeroed"
+		for ((r=0; r<NROWS; ++r)); do
+			for ((c=0; c<NCOLS; ++c)); do
+				((cell=r*NCOLS+c))
+				if (( seats[cell] == 2 )); then
+					# diagonal up left
+					r1=$((r-1))
+					c1=$((c-1))
+					while ((r1>=0 && c1>=0)); do
+						((control[r1*NCOLS+c1]++));
+						#echo up >&2
+						((seats[r1*NCOLS+c1] != 0)) && break
+						((r1--))
+						((c1--))
+					done
+					# diagonal up right
+					r1=$((r-1))
+					c1=$((c+1))
+					while ((r1>=0 && c1<NCOLS)); do
+						((control[r1*NCOLS+c1]++));
+						((seats[r1*NCOLS+c1] != 0)) && break
+						((r1--))
+						((c1++))
+					done
+					# diagonal down left
+					r1=$((r+1))
+					c1=$((c-1))
+					while ((r1<NROWS && c1>=0)); do
+						((control[r1*NCOLS+c1]++));
+						((seats[r1*NCOLS+c1] != 0)) && break
+						((r1++))
+						((c1--))
+					done
+					# diagonal down right
+					r1=$((r+1))
+					c1=$((c+1))
+					while ((r1<NROWS && c1<NCOLS)); do
+						((control[r1*NCOLS+c1]++));
+						((seats[r1*NCOLS+c1] != 0)) && break
+						((r1++))
+						((c1++))
+					done
+					# line left
+					c1=$((c-1))
+					while ((c1>=0)); do
+						((control[r*NCOLS+c1]++));
+						((seats[r*NCOLS+c1] != 0)) && break
+						((c1--))
+					done
+					# line right
+					c1=$((c+1))
+					while ((c1<NCOLS)); do
+						((control[r*NCOLS+c1]++));
+						((seats[r*NCOLS+c1] != 0)) && break
+						((c1++))
+					done
+					# column up
+					r1=$((r-1))
+					while ((r1>=0)); do
+						((control[r1*NCOLS+c]++));
+						((seats[r1*NCOLS+c] != 0)) && break
+						((r1--))
+					done
+					# column down
+					r1=$((r+1))
+					while ((r1<NROWS)); do
+						((control[r1*NCOLS+c]++));
+						((seats[r1*NCOLS+c] != 0)) && break
+						((r1++))
+					done
+				fi
+			done
+		done
+		for ((r=0; r<NROWS; ++r)); do
+			for ((c=0; c<NCOLS; ++c)); do
+				((cell=r*NCOLS+c))
+				#((ccell=(r+1)*(NCOLS+2) + c+1))
+				case ${seats[cell]} in
+					0) continue
+					   ;;
+					1) if (( control[cell] == 0 )); then
+						   ((++changed))
+						   seats[cell]=2
+					   fi
+					   ;;
+					2) if (( control[cell] >= 5 )); then
+						   ((++changed))
+						   seats[cell]=1
+					   fi
+				esac
+				#printf "r=%d c=%d cell=%d val=%s\n" "$r" "$c" "$cell" "${seats[cell]}" >&2
+			done
+			#echo >&2
+		done
+
+		for ((r=0; r<NROWS; ++r)); do
+			for ((c=0; c<NCOLS; ++c)); do
+				((cell=(r*(NCOLS))+c))
+				((seats[cell] == 2)) && ((seated++))
+			done
+		done
+		#print_control
+		#print_seats
+
+		((loop++))
+	done
+	echo "$seated"
+}
+
+
+
+readarray -t rowsstr
+
+for ((i=0; i<${#rowsstr[@]}; ++i)); do
+	rowsstr[i]=${rowsstr[i]//./0}
+	rowsstr[i]=${rowsstr[i]//L/1}
+	rowsstr[i]=${rowsstr[i]//#/2}
+done
+
+NCOLS=${#rowsstr[0]}
+NROWS=${#rowsstr[@]}
+SIZE=$((NCOLS * NROWS))
+
+printf -v zeroed '%0.s0 ' $(seq 1 $SIZE)
+
+# split arrays in integers
+for ((r=0; r<NROWS; ++r)); do
+	srow="${rowsstr[r]}"
+	nrow=()
+	for ((c=0 ; c<NCOLS ; c++ )); do
+		nrow+=("${srow:c:1}")
+	done
+	rows[r]="${nrow[*]}"
+done
+read -ra seats <<< "${rows[*]}"
+
+#echo "S=${#seats[@]} C=${#control[@]}"
+#print_seats
+
+res=$(run)
+printf "%s : res=%d\n" "$CMD" "$res"
+
+exit 0