#!/usr/bin/env bash

FILE=input
LEN=$( head -1 "$FILE" | sed -E 's/(.)/\1\ /g' | awk '{printf NF}' )

read -r -a MAP_ARRAY <<< "$( < "$FILE" sed -E 's/(.)/\1\ /g' | paste -s -d ' ' )"
read -r -a SHADOW_ARRAY <<< "$( < "$FILE" sed -E 's/(.)/\1\ /g' | paste -s -d ' ' )"
#printf "MAP_LEN: %s, NF: %s\n" "${#MAP_ARRAY[@]}" "$LEN" >&2

for CHAR in $( < "$FILE" grep -Eo '[^\.]' | sort -u | paste -s -d' ' )
do
  # Get indices for antennae
  LINE="$( 
    for (( i=0; i<${#MAP_ARRAY[@]}; i++ ))
    do
      if [[ ${MAP_ARRAY[i]} == "$CHAR" ]]
      then
        printf "%s " "$i"
      fi
    done
  )"
  printf "%s\n" "$LINE" >&2
  read -r -a IDX_ARRAY <<< "$LINE"
  #printf "idx:  %s " "${IDX_ARRAY[@]}" >&2
  #printf "\n" >&2

  # Get all combinations
  for (( i=0; i<${#IDX_ARRAY[@]}-1; i++ ))
  do
    A=${IDX_ARRAY[i]}
    for (( j=i+1; j<${#IDX_ARRAY[@]}; j++ ))
    do
      B=${IDX_ARRAY[j]}
      DIFF=$(( B - A ))
      HEAD=$(( A - DIFF ))
      TAIL=$(( B + DIFF ))
      printf "char: %s, i: %s, j: %s, DIFF: %s, HEAD: %s, TAIL: %s\n"  "$CHAR" "$A" "$B" "$DIFF" "$HEAD" "$TAIL" >&2
      for VALUE in $HEAD $TAIL
      do
        if [[ $VALUE -gt ${#MAP_ARRAY[@]} ]] || [[ $VALUE -lt 0 ]]
	then
          continue
	fi
	SHADOW_ARRAY[VALUE]=X # Mark on shadow map
      done
    done
  done
  unset IDX_ARRAY

done
COUNT=0
for (( i=0; i<${#SHADOW_ARRAY[@]}; i++ ))
do
  if [[ ${SHADOW_ARRAY[i]} == "X" ]]
  then
    (( COUNT++ ))
  fi
done
printf "%s\n" "$COUNT"
printf "%s" "${SHADOW_ARRAY[@]}" | fold -w "$LEN" | sed -E 's/(.)/\1\ /g'