Add Day 4

4/1/solution.sh

@@ -0,0 +1,45 @@
+#!/usr/bin/env bash
+
+set -o errexit
+set -o nounset
+set -o pipefail
+if [[ "${TRACE-0}" == "1" ]]; then
+  set -o xtrace
+fi
+
+cd "$(dirname "$0")"
+
+main ()
+{
+  declare -i sum=0
+  while read -r line; do
+    declare -a winning=() mine=() mywinning=()
+    declare -i card_sum=0
+    echo "$line"
+    stripped=$(sed 's/Card\s\{1,3\}[0-9]\{1,3\}: //' <<< "${line}")
+    winning+=($(cut -d '|' -f 1 <<< "${stripped}"))
+    mine+=($(cut -d '|' -f 2 <<< "${stripped}"))
+    for number in "${mine[@]}"; do
+      for w in "${winning[@]}"; do
+        if [[ ${number} -eq ${w} ]]; then
+          mywinning+=("${number}")
+          break
+        fi
+      done
+    done
+    echo mywwinning ${mywinning[@]}
+    for number in "${mywinning[@]}"; do
+      if [[ card_sum -eq 0 ]]; then
+        card_sum=$((card_sum+1))
+      else
+        card_sum=$((card_sum*2))
+      fi
+    done
+    echo "card sum: $card_sum"
+    sum=$((sum+card_sum))
+    echo "sum: ${sum}"
+  done < input.txt
+  echo "${sum}"
+}
+
+main "$@"