Day 14, Bash & C

day14/ex1.bash

@@ -0,0 +1,31 @@
+#!/bin/bash
+#
+# ex1.bash: Advent2020 game, day 14/game 1.
+
+CMD=${0##*/}
+shopt -s extglob
+declare -A mem
+declare -i pos
+declare ORMASK ANDMASK
+declare mask=""
+
+while read -r line; do
+	line=${line// /}
+	eval "$line"
+
+	if [[ $line =~ ^mask ]]; then
+		ORMASK=2\#${mask//X/0}
+		ANDMASK=2\#${mask//X/1}
+	else
+		[[ $line =~ ^.*\[([0-9]+)\].* ]]
+		pos=${BASH_REMATCH[1]}
+		((mem[$pos] &= ANDMASK))
+		((mem[$pos] |= ORMASK))
+	fi
+done
+SUM=0
+for i in "${!mem[@]}"; do
+	((SUM+=${mem[$i]}))
+done
+printf "%s : res=%d\n" "$CMD" "$SUM"
+exit 0