[Linux/리눅스] shell bash 를 이용해서 짝수 누적합출력하기

#! /bin/bash
echo -n "aaa:"
read A
B=11
c=0
while [ $A -lt $B ]
        do
        if [ `expr $A % 2` -eq 0 ]
                then
                echo $A
                c=`expr $c + $A`
        fi
        A=`expr $A + 1`
done
        echo $c
        echo "end"
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