#!/bin/sh
read START
read END
read MATCH

REND=$(grep -n "$END" lines | tail -1 | cut -d":" -f 1)
RSTART=$(grep -n "$START" lines | head -1 | cut -d":" -f 1)

echo $REND $RSTART
sed $RSTART,$REND!d lines | grep "$MATCH"