win

day/02/part2.sh

@@ -49,6 +49,44 @@ function check_is_safe() {
   echo "${fun_is_safe}"
 }
 
+function check_list() {
+  local line_split=("$@")
+
+  # start with the first val
+  prev_val="${line_split[0]}"
+
+  local is_safe=1
+
+  # if positive, going up, if negative, going down!
+  is_up_down="$((line_split[1] - line_split[0]))"
+
+  if [[ "${is_up_down}" -ge 0 ]]; then
+    debug_echo "Initially going up"
+  else
+    debug_echo "Initially going down"
+  fi
+
+  for idx in "${!line_split[@]}"; do
+    [[ "${idx}" -eq 0 ]] && continue
+    debug_echo "index $idx"
+    v="${line_split[${idx}]}"
+    debug_echo "checking [${v}] against previous [${prev_val}]"
+    test_is_safe=$(check_is_safe "${is_up_down}" "${v}" "${prev_val}")
+
+    debug_echo "safe val ${test_is_safe}"
+
+    if [[ "${test_is_safe}" -eq 0 ]]; then
+      # normally we fail this set
+      is_safe=0
+    fi
+
+    # we skip the re-assign once to 'skip' a number
+    prev_val=$v
+  done
+
+  echo "${is_safe}"
+}
+
 while read -r l; do
   echo "reading new line [$l]"
 
@@ -56,56 +94,22 @@ while read -r l; do
   read -ra line_split <<< "${l}"
   unset IFS
 
-  # start with the first val
-  prev_val="${line_split[0]}"
-
-  is_safe=2
-
-  # if positive, going up, if negative, going down!
-  is_up_down="$((line_split[1] - line_split[0]))"
-
-  safety_trigger=1
-
-  if [[ "${is_up_down}" -ge 0 ]]; then
-    echo "Initially going up"
-  else
-    echo "Initially going down"
-  fi
+  is_safe=$(check_list "${line_split[@]}")
 
+  if [[ "${is_safe}" -eq 0 ]]; then
     for idx in "${!line_split[@]}"; do
-    [[ "${idx}" -eq 0 ]] && continue
-    echo "index $idx"
-    v="${line_split[${idx}]}"
-    echo "checking [${v}] against previous [${prev_val}]"
-    test_is_safe=$(check_is_safe "${is_up_down}" "${v}" "${prev_val}")
-
-    debug_echo "safe val ${test_is_safe}"
-
-    if [[ "${test_is_safe}" -eq 0 ]]; then
-      # normally we fail this set
-      is_safe=$((is_safe - 1))
-    fi
-
-    if [[ "${test_is_safe}" -eq 0 ]] && [[ "${safety_trigger}" -eq 1 ]]; then
-      # but we let 1 happen if the trigger hasnt... triggered
-      safety_trigger=0
-      if [[ "${idx}" -eq 1 ]]; then
-        # we may have to re-calculate is_up_down!
-        is_up_down="$((line_split[2] - line_split[0]))"
-        echo "allowing flip up/down"
-      fi
-      echo "-------------------"
-      echo "allowing 1 failure!"
-      echo "-------------------"
-    else
-      # we skip the re-assign once to 'skip' a number
-      prev_val=$v
+      # remove each item from the set and try again
+      new_line_split=("${line_split[@]:0:${idx}}" "${line_split[@]:$((idx + 1))}")
+      echo "${new_line_split[@]}"
+      is_retry_safe=$(check_list "${new_line_split[@]}")
+      if [[ "${is_retry_safe}" -gt 0 ]]; then
+        is_safe=1
+        break
       fi
     done
-
-  if [[ "${is_safe}" -gt 0 ]]; then
-    safe_count=$((safe_count + 1))
   fi
+
+  safe_count=$((safe_count + is_safe))
 done <"$FILE_IN"
 
 echo "final safe count ${safe_count}"