2. To print all prime numbers between m & n

echo "enter the lower limit m value"
read m
echo "enter the upper limit n value"
read n
echo "Prime Numbers between $m and $n are"
while [ $m -le $n ]
do
    flag=1
    i=2
    while [ $i -lt $m ]
    do
        if [ `expr $m % $i` -eq 0 ]
        then
            flag=0
            break
        else
            i=`expr $i + 1`
        fi
    done
   
    if [ $flag -eq 1 ]
    then
        echo $m
    fi

m=`expr $m + 1`
done