Array Length is 1 in Bash scripting

Question

In the below code, the array length is 1.

Could anyone explain why, as grep output will displayed in each new line but when it is stored in the array, the array length will be 1.

How to display each line reading the array?

#!/bin/bash

NUM=()
SHORT_TEXT=()
LONG_TEXT=()

#cat /tmp/dummy2 | 
while read NUM 
do
    LONG_TEXT+=$(grep $NUM -A4 RtpLogShm.Msg | grep -vi abate | grep ^LG)
    done < /tmp/dummy2

    #cat /tmp/dummy1 | 
    while read LINE
    do
        NUM+=$(echo $LINE | awk -F':' '{print $1}')
        SHORT_TEXT+=$(echo $LINE | awk -F':' '{print $2}')
        done < /tmp/dummy1

        printf "[%s]\n" "${LONG_TEXT[@]}"
    done
done

Answer 1

在bash中，追加到数组的语法是（例如，我们要将存储在${new_element}的元素追加到现有数组${array[@]} ）：

array=("${array[@]}" "${new_element}")