Question

Pset3 Problem 3 I don't understand what the code is supposed to do? Can someone please explain in simpler terms?

Answer 1

Here is link to the pset http://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-00-introduction-to-computer-science-and-programming-fall-2008/assignments/pset3.pdf

Answer 2

I made the program without really knowing in full how the code works. I understand what the outputs should be and how to get em to output but I don't understand why the outputs are what they are.

Answer 3

on the last page of the link you posted, , it talks about substitution or finding matches,
does that help in understanding the use of the output?

Answer 4

This is what I did http://dpaste.com/hold/528512/. Its kind of hard to explain I understand the syntax of how the program works but I guess what I don't understand is the mathematics on how the n+m+1==k gives you possible solutions

Answer 5

sorry forgot to say in my program its if n+length+1==k but yea thats the part I don't understand.

Answer 6

i'm looking at it now. one sec

Answer 7

i'm starting to think that n+m+1=k might not be true for all possible situations especially empty string and "blah blah.. " case

Answer 8

but thats what it said to do in the pset directions. Can you explain what it actually does to me because I only put it in because thats what the directions said I have no clue what it means.

Answer 9

let's take the example 'a' and 'gc'
'a' is at index 5 , and 5+ (length of a)+ 1 gives 7 the index of gc in the target string or the large string "
ATGACATGCA"

Answer 10

does this help any?

Answer 11

first tuple really is ( 0,3,5,9) and 0,3,9 don't satisfy the condition n+m+1 = k - > 0+1+1, 3+1+1, 9+1+1 -> 2,5,11 is not equal to 7 (index of gc in the target string)

Answer 12

yes this somewhat helps how would I fix it so that it doesn't give wrong answers?

Answer 13

what part of n+m+1 = k doesn't help at the moment?
what input gives you errors? is that input appropriate at all? Remember it says split the key string into two parts

Answer 14

i looked at the code in http://dpaste.com/hold/528512/
you can remove "count" from subStringMatchExact function