#!/bin/bash

declare -A dots
folds=()

while read line; do
  if [[ $line == *','* ]]; then
    dots[$line]=1
  else
    folds+=( ${line#fold along } )
  fi
done

fold=${folds[0]}
fold_axis=${fold%=*}
fold_coord=${fold#*=}
new_dots=()
todel_dots=()

for dot in ${!dots[@]}; do
  dot_x=${dot%,*}
  dot_y=${dot#*,}
  if [[ $fold_axis == 'x' ]]; then
    if [ $dot_x -gt $fold_coord ]; then
      new_dots+=( "$((fold_coord*2-dot_x)),$dot_y" )
      todel_dots+=( $dot )
    fi
  else
    if [ $dot_y -gt $fold_coord ]; then
      new_dots+=( "$dot_x,$((fold_coord*2-dot_y))" )
      todel_dots+=( $dot )
    fi
  fi
done

for todel_dot in ${todel_dots[@]}; do
  unset dots[$todel_dot]
done

for new_dot in ${new_dots[@]}; do
  dots[$new_dot]=1
done

echo ${#dots[@]}