Page 426 - Computer science 868 Class 12
P. 426
D. Long answer type questions/programs:
1. Design a class Unique to check if a given number is Unique number or not. Unique numbers have no repeating digits in it. The
details are given below:
Class Name : Unique
Data Member
int n : To store number
Member methods
Unique(int a) : Constructor to assign n = a
int count(int d, int a) : Counts and returns how many times digit 'd' occurs in numbers 'a'
using recursion
void check() : Calls count(int, int) and prints if the number is unique or not
Define the class giving details of the methods given above. Also, write the main method to create object and call other
methods.
Ans. class Unique
{
int n;
Unique(int a)
{
n = a;
}
int count(int d, int a)
{
if (a == 0) //base case
return 0;
else if (a%10==d) //if digit exists
return 1+count(d, a/10); //recursive case
else
return count(d, a/10); //if digit does not exist
}
void check()
{int c;
for(int i=0; i<=9; i++)
{
c=count(i, n); //calling method
if(c>1)
break;
}
if(c>1)
System.out.println(n+ "is not unique");
else
System.out.println(n+ "is unique");
}
public static void main(int x)
{
Unique ob=new Unique(x);
ob. check();
}
}
}
424424 Touchpad Computer Science-XII

