This code is meant to search a set of folders containing files with name format DD-MM-YYYY and renames them as YYYY-MM-DD. However, while this loop works fine on the first iteration, it doesn't interpret the regular expression in the second run.

```
#!/usr/bin/env bash
WORKING_DIRS=( "/directory1" "/directory2" )
for WORKING_DIR in ${WORKING_DIRS[@]}
do
echo "WORKING DIRECTORY : $WORKING_DIR"
echo "--------------------------------------------------------"
for entry in "$WORKING_DIR"/[0-9][0-9]-[0-9][0-9]-[0-9][0-9][0-9][0-9].doc
do
    IFS='/'
    read -r -a array <<< "$entry"
    file_name="${array[${#array[@]}-1]}"
    echo "$file_name"
    IFS='.'
    read -r -a file <<< "$file_name"
    echo "OLD DATE: $file"
    IFS='-'
    read -r -a file_split <<< "${file[0]}"
    day=${file_split[0]}
    month=${file_split[1]}
    year=${file_split[2]}
    new_date="$year-$month-$day"
    echo "NEW DATE : $new_date"
    mv "$WORKING_DIR"/"$file_name" "$WORKING_DIR"/"$new_date".doc
done
done

```