day05

day05.sh

@@ -0,0 +1,76 @@
+#!/usr/bin/env bash
+unset PATH; readonly PATH
+source ./utils/main.sh
+
+p1() {
+  local input="$1" result=0 pages=() line
+  local -A rules=()
+
+  while read -r line; do
+    [[ -z "$line" ]] && continue
+    case "$line" in
+      [0-9]*\|[0-9]*) rules+=([${line%|*}]="${rules["${line%|*}"]:-} ${line#*|}");;
+      *) pages+=("$line");;
+    esac
+  done <<< "$input"
+
+  for page in "${pages[@]}"; do
+    local page_arr
+    IFS=, read -ra page_arr <<< "$page"
+
+    for ((i=0; i < ${#page_arr[@]}; i++)); do
+      local current_page="${page_arr[i]}"
+      local current_rules="${rules["$current_page"]:-}"
+      [[ -z "${current_rules:-}" ]] && continue
+
+      for ((j=0; j < ${#page_arr[@]}; j++)); do
+        [[ "$current_rules" =~ ${page_arr[j]} ]] && ((j < i)) && continue 3
+      done
+    done
+    
+    result="$((result + ${page_arr[$(((${#page_arr[@]} - 1) / 2))]}))"
+  done
+
+  printf '%s' "$result"
+}
+
+p2() {
+  local input="$1" result=0 pages=() line
+  local -A rules=()
+
+  while read -r line; do
+    [[ -z "$line" ]] && continue
+    case "$line" in
+      [0-9]*\|[0-9]*) rules+=([${line%|*}]="${rules["${line%|*}"]:-} ${line#*|}");;
+      *) pages+=("$line");;
+    esac
+  done <<< "$input"
+
+  for page in "${pages[@]}"; do
+    local page_arr incorrect='false'
+    IFS=, read -ra page_arr <<< "$page"
+
+    for ((i=0; i < ${#page_arr[@]}; i++)); do
+      local current_page="${page_arr[i]}"
+      local current_rules="${rules["$current_page"]:-}"
+      [[ -z "${current_rules:-}" ]] && continue
+
+      for ((j=0; j < ${#page_arr[@]}; j++)); do
+        if [[ "$current_rules" =~ ${page_arr[j]} ]] && ((j < i)); then
+          local removed_elem="${page_arr[j]}"
+          read -ra page_arr <<< "${page_arr[*]/"$removed_elem"}"
+          page_arr=("${page_arr[@]:0:$i}" "$removed_elem" "${page_arr[@]:$i}")
+          incorrect='true'
+          ((i--))
+          ((j--))
+        fi
+      done
+    done
+    
+    [[ "$incorrect" == 'true' ]] && result="$((result + ${page_arr[$(((${#page_arr[@]} - 1) / 2))]}))"
+  done
+
+  printf '%s' "$result"
+}
+
+main "$@"