Something

filelength=`wc -l array.txt`                                                                while ((i=1;i<=filelength;i+=1))do if sed -n '$i Amount' array.txt	for ((j=i;j<=filelength;j+=1)); sed -n '$i /<string>.*</string>/p' array.txt	for ((i=1;i<=filelength;i+=1))done