bash port scanner v2 by light !v1UPDATE!

#!/bin/bash
# By: LiGhT
# Bash Port Scanner v2

if [ $# != 5 ]; then
echo -e "\e[0;32mUsage: [start ip] [end ip] [port to scan] [input file] [output file]\e[1;37m"
exit 0
fi
if [ -f /usr/bin/nc ]; then
echo -e "\e[0;32mBash Port Scanner v2... IP GEN STARTED!.. Be patient(bigger ranges will take longer)\e[1;37m"
else
exit 0
fi
IPLO=(`echo "$1" | awk '{split($1,a,"."); print a[1]" "a[2]" "a[3]" "a[4]}'`)
IPHI=(`echo "$2" | awk '{split($1,a,"."); print a[1]" "a[2]" "a[3]" "a[4]}'`)

OCTA=${IPLO[0]}
OCTB=${IPLO[1]}
OCTC=${IPLO[2]}
OCTD=${IPLO[3]}
OCTAHI=${IPHI[0]}
OCTBHI=${IPHI[1]}
OCTCHI=${IPHI[2]}
OCTDHI=${IPHI[3]}
OCTDMAX=255
FINISHED=0

for i in 0 1 2 3
do
        if [ -z "${IPLO[$i]}" ] || [ -z "${IPHI[$i]}" ]; then
                exit 1
        elif [ "${IPLO[$i]}" -gt "255" ] || [ "${IPHI[$i]}" -gt "255" ];then
                echo "You fucked up on your ip ranges"
                exit 1
        fi

done

until [ "$FINISHED" -eq "1" ]; do #check
        if [ "$OCTA" -eq "$OCTAHI" ] && \
           [ "$OCTB" -eq "$OCTBHI" ] && \
           [ "$OCTC" -eq "$OCTCHI" ]; then
                OCTDMAX=$OCTDHI
        fi

        while [ "$OCTD" -le "$OCTDMAX" ]; do
                echo "$OCTA.$OCTB.$OCTC.$OCTD" >> $4 #outputs ips into file
                if [ "$OCTA" -eq "$OCTAHI" ] && \
                   [ "$OCTB" -eq "$OCTBHI" ] && \
                   [ "$OCTC" -eq "$OCTCHI" ] && \
                   [ "$OCTD" -eq "$OCTDHI" ]; then
                        FINISHED=1
                fi
                OCTD=$(( $OCTD + 1 )) #changing value of variable
        done

        OCTC=$(( $OCTC + 1 ))
        OCTD="0"

        if [ "$OCTC" -gt "255" ]; then #check
                OCTB=$(( $OCTB + 1 ))
                OCTC="0"
        fi

        if [ "$OCTB" -gt "255" ]; then #check
                OCTA=$(( $OCTA + 1 ))
                OCTB="0"
        fi

        if [ "$OCTA" -gt "255" ]; then #check
                FINISHED=1
        fi
done
echo -e "\e[0;32mIPs Found:\e[1;37m $(cat $4 | wc -l)\e[1;37m"
echo -e "\e[0;32mStarting Portscan!\e[1;37m"
while IFS='' read -r line || [[ -n "$line" ]]; do
        if [[ $(nc -v -z -w 1 $line $3 | grep succeeded | grep -v time | grep -v fail) != "" ]]
        then
        echo "Host: $line | Port: $3" && echo $line >>$5 #prints ip w/ open port and sends ip to an active ip list
        fi
done < "$4"
exit 0