Page 257 - Computer science 868 Class 12
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8.12.2 Programs Implementing the Constructor


                  Program 8      A sequence of Fibonacci strings is generated as follows:
                                 S  = “a”, S  = “b”, S  = S (n-1)  + S (n-2)  where ‘+’ denotes concatenation. Thus the sequence is:
                                                 n
                                          f
                                  0
                                 a, b, ba, bab, babba, babbabab,……. n terms.
                                 Design a class FiboString to generate Fibonacci strings. Some of the members of the class are
                                 given below.
                                 Class name                      :   FiboString
                                 Data Members/Instance variables
                                 x                               :   to store the first string
                                 y                               :   to store the second string
                                 z                               :   to store the concatenation of the previous two strings
                                 n                               :   to store the number of terms
                                 Member Functions/methods
                                 FiboString()                    :   constructor to assign x=“a”, y=“b” and z=“ba”
                                 void accept()                   :   to accept the number of terms ‘n’
                                 void generate()                 :    to  generate  and  print  the  Fibonacci  strings.  The  sum
                                                                    of (‘+’, e.g., concatenation) first two strings is the third
                                                                    string, e.g., “a” is the first string, “b” is the second string,
                                                                    then the third will be “ba”, and the fourth will be “bab”
                                                                    and so on
                                 Specify the class FiboString giving details of the constructor(), void accept() and void generate().
                                 Define the main() function to create an object and call the functions accordingly to enable the
                                 task.

                   1       import java.util.*;

                   2       class FiboString
                   3       {
                   4           String x,y,z;

                   5           int n;
                   6           FiboString()    // No Argument constructor

                   7           {
                   8               x="a";

                   9               y="b";
                  10               z="ba";

                  11           }
                  12

                  13           void accept()
                  14           {

                  15               Scanner Sc = new Scanner (System.in);





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