c program for padovan string

Padovan series are positive integers obtained by the following process: The Padovan series is the sequence of integers P(n) defined by the initial values P(0) = P(1) = P(2) = 1, and the recurrence relation P(n) = P(n - 2) + P(n - 3).
Write a program to generate the Padovan series from n to m.
 
Constraints:

• n >=0 and m <=49.
• m >= n.

If the given inputs are invalid or out of range, then return -1 .
 
Example 1:
Input
from = 5
to = 10
 
Output:
returns {3, 4, 5, 7, 9, 12}
 
Explanation:

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P(0
) = P(1
) = P(2
) = 1
, and
 the recurrence relation P(n) = P(n - 2
) + P(n - 3
). 
p(5
) = p(5
-2
) + p(5
-3
) 
        = p(3
) + p(2
) -------- (1
) 
p(3
) = p(3
-2
) + p(3
-1
) 
        = p(1
) + p(2
) 
        = 1
 + 1
 
        = 2
 
Substitute in
 (1
) 
p(5
) = 2
 + 1
 
        = 3
 

Similarly the recurrence should continue for the remaining positions.
 
Example 2:
Input
from = 45
to = 60
 
Output
Returns {-1}
 
CODE TO IMPLEMENT THIS:

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import
 java.util.Scanner;
import
 java.util.ArrayList;
 
public
 class
 Padovan
Series
{
    public
 static
 void
 main(String
[] arg)
    {
        Scanner read = new
 Scanner(System.in);
        System.out.println("
Enter starting no. : "
);
        int
 start = read.nextInt();
        System.out.println("
Enter ending no. : "
);
        int
 end = read.nextInt();
        int
[] ans = getSeries(start, end);
        System.out.println("
Padovan
 series : "
);
        for
 (int
 a : ans)
            System.out.print(a + "
 "
);
    }
 
    public
 static
 int
[] getSeries(int
 s, int
 e)
    {
        ArrayList list = new
 ArrayList();
        int
 i, j = 0
;
        for
 (i = s; i <= e; i++, j++)
            list.add(getPadovan
(i));
        int
[] ans = new
 int
[j];
        for
 (i = 0
; i < j; i++)
            ans[i] = list.get(i);
        return
 ans;
    }
 
    public
 static
 int
 getPadovan
(int
 p)
    {
        if
 (p == 0
 || p == 1
 || p == 2
)
            return
 1
;
        return
 (getPadovan
(p - 2
) + getPadovan
(p - 3
));
    }
}