//final_1 is a list of Identifier which I need to find corresponding files(four lines) in x(x is the file) and write following four lines in a new file.
//because the order of the identifier is the same, so after I find the same identifier in x , the next time I want to start from next index in x,which will save time. That is to say , when the if command satisfied ,it can automatically jump out out the second while loop and come to the next identifier of final_1 ,meanwhile the j should start not from the beginning but the position previous. //when I run the code it takes too much time more than one hour and give the wrong result....so could you help me make some improvement of the code? i=0 offset_1=0 while i <len(final_1): j = offset_1 while j <len(x1): if final_1[i] == x1[j]: new_file.write(x1[j]) new_file.write(x1[j+1]) new_file.write(x1[j+2]) new_file.write(x1[j+3]) offset_1 = j+4 quit_loop="True" if quit_loop == "True":break else: j=j +1 i=i+1 -- http://mail.python.org/mailman/listinfo/python-list