#!/bin/bash

P1=$1
P2=$2

case "$P1" in
(*/)
	;;
(*)
	P1=$P1/
esac

while true
do
	case "$P1" in
	(*/*)
		case "$P2" in
		(*/*)
			if [ "${P1%%/*}" = "${P2%%/*}" ]
			then
				P1=${P1#*/}
				P2=${P2#*/}
			else
				break
			fi
			;;
		(*)
			break
		esac
		;;
	(*)
		break
	esac
done

while true
do
	case "$P1" in
	(*/*)
		P1=${P1#*/}
		P2=../$P2
		;;
	(*)
		break
	esac
done

echo "$P2"
