QUILT - Little Quilt
Little Quilt is a small language introduced by Ravi Sethi in his book ‘Programming Languages’.
Here, a restricted version of Little Quilt is presented. The language is defined by the following BNF grammar:
< QUILT > ::= A | B | turn(< QUILT >) | sew(< QUILT >,< QUILT >)
A and B represent the two primitive quilts. Each primitive quilt corresponds to a matricial arrangement of 2 × 2 characters. turn() and sew() are operations over quilts.
The instruction turn(x) turns the quilt x 90 degrees clockwise. The following table illustrates the primitive quilts as well as examples of the effect of the turn() operation:
Accordingly, the instruction sew(x,y) sews quilt x to the left of quilt y. Both x and y must have the same height, otherwise an error will be generated. The following figure represents the result of sew(A,turn(B)):
while the sew(turn(sew(B,turn(B))),A) generates an error message.
Your job is to build an interpreter of the Little Quilt language.
The input file will be a text file containing different Little Quilt expressions, each one ended by a semicolon character (;). Space and new line characters must be ignored; this means that an expression may span several lines.
The output file contains the quilts produced as a result of interpreting the input expressions.
Each quilt must be preceded by a line, left aligned, with the format
where i is the quilt number, starting at 1. If the expression interpretation generates and error, the word
must be printed.
Input: sew(turn(sew(B,turn(B))), turn(sew(turn(B),B))) ;
sew(turn(sew(B,turn(B))),A); sew(turn(sew(A,turn(A))), turn(turn(
turn(sew(A,turn(A)))))) ; Output: Quilt 1: ||-- ||-- --|| --|| Quilt 2: error Quilt 3: \\// +\/+ +/\+ //\\
What is the data's range? What size will the final graph be ?
Hi I need the solve of this problem :( I dont have time for solve, its for school, please send me the code in Java, send me to firstname.lastname@example.org
Can we assume the input is valid? i mean, there will be no expressions like sew(a); ?
abhijith reddy d:
A Tedious one !!