Assignment 6

This exercise is based on string manipulation and handling of two-dimensional arrays. You are given a text file. Your problem is to adjust the spaces in each line in such a way that the resulting text is justified (both at the left and at the right). Here is our proposal of an algorithm that you should use in order to solve the problem.

• First read the input file and store the lines in a two-dimensional character array with each line stored in a single row of the array.

• The text is divided into paragraphs. Two consecutive paragraphs are separated by a blank line.

• The last line in a paragraph is not to be justified. Also a blank line is not to be justified.

• Finally suppose that you have a non-blank line which is not the last line of a paragraph. If the length of this line is already larger than the target width, then do not perform any processing of this line. Otherwise, increase the sizes of the inter-word gaps so that the resulting line has a width equal to the target width.

  Assume that len denotes the initial length of the line and that the line initially contains nsp number of inter-word spaces. You have to add a total of

     extra = target_width - len
  

  number of additional spaces in the line. In order that the insertion leads to (aesthetically) good-looking paragraphs, it is necessary to distribute the extra new spaces more or less uniformly among the nsp inter-word gaps. Let

     q = extra / nsp (integer division).
  

  First insert q additional spaces in each of the nsp gaps. If extra is not an integral multiple of nsp, this still leaves us with

     r = extra - q * nsp
  

  spaces to be inserted. If the line has an odd number in the current paragraph, add another single space in each of the first r gaps. On the other hand, if the line has an even number in the current paragraph, add a single space in each of the last r gaps.

  Here is an example. Consider the following line:

     Deciding the truth of a statement in a formal system was called the
  

  which has a length of 67. Assume that the target width is 75. You have to add 8 extra spaces to the line. The line contains 12 inter-word gaps. If the line has an odd number in the paragraph, then the leftmost 8 inter-word gaps should be increased from one space to two spaces, else the rightmost 8 gaps need be so increased. In the former case, the line would look like

     Deciding  the  truth  of  a  statement  in  a  formal system was called the
  

  and in the latter case it would look like

     Deciding the truth of a  statement  in  a  formal  system  was  called  the
  

  If we started with a smaller line like

     Deciding the truth of a statement in a formal system was called
  

  that needs 75-63=12 spaces to be added among 11 gaps, the line after justification would look like

     Deciding   the  truth  of  a  statement  in  a  formal  system  was  called
  

  or

     Deciding  the  truth  of  a  statement  in  a  formal  system  was   called
  

  depending on its position in the paragraph.

• Replace each row of your two-dimensional array by its justified version using the above rules.

• Print the resulting justified text line-by-line.

• Take the target width to be 75. There is a total of 230 lines in this file and each line has a width no bigger than 75.

The following should be the output of your program for the fourth paragraph of the input file.

   The  design  of  the  first commercially available mechanical calculator is
   attributed to Leibnitz (1671) (the same bloke who  invented  calculus).  It
   was  completed  in  1694  and  Leibnitz  demonstrated,  for the first time,
   that  binary  arithmetic  was  superior  to  decimal   arithmetic   as   it
   simplifies  machine  construction.  Leibnitz's machine could add, subtract,
   multiply, divide and even  find  square  root.  Leibnitz's  machine  was  a
   full  adder  (you'll  learn  about  a  full  adder in your Digital Hardware
   Design course), in which the carry was saved in the form  of  the  position
   of  a  lever.  A  working  model of this machine was exhibited at the Royal
   Society of  London  in  1794,  but  it  was  somewhat  unreliable.  It  was
   commercially available in 1820.

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