rename repo, subdir for yearly challenges

2020/day06/ex1.bash

@@ -0,0 +1,55 @@
+#!/bin/bash
+#
+# ex1.bash: Advent2020 game, day 6/game 1.
+
+CMD=${0##*/}
+shopt -s extglob
+declare -A Q=()
+
+function reset_array() {
+	for elt in {a..z}; do
+		Q[$elt]=0
+	done
+}
+function count_array() {
+	local -i count
+	for elt in "${!Q[@]}"; do
+		(( Q[$elt] > 0 )) && ((count++))
+	done
+	echo $count
+}
+
+function set_array() {
+	local str="$1"
+	local c
+
+	for ((i=0; i<${#str}; ++i)); do
+		c=${str:$i:1}
+		if [[ "$c" =~ [a-z] ]]; then
+			Q[$c]=1
+		fi
+	done
+}
+
+declare -i people=0 group=0 count=0
+
+function calcgroup() {
+	((group++))
+	((count += $(count_array)))
+	((people=0))
+	reset_array
+}
+
+while read -r line; do
+	if [[ -z "$line" ]]; then
+		calcgroup
+		continue
+	fi
+	((people++))
+	set_array "$line"
+done
+calcgroup
+
+printf "%s : groups=%d count=%d\n" "$CMD" $group $count
+
+exit 0