There are three piles of pens. A pens in the first pile and B pens in the second Pile.Find the minimum number of pens that should be there in the third pile so that sum of all three piles produces either a prime number or unity.
Note: there should be atleast one pen in the third pile.
Example 1:
Input: A = 1, B = 3
Output: 1
Explanation: A + B + K = prime
K = 1, 1 + 3 + 1 = 5.So answer = 1
becuase 5 is minimum possible prime.
Example 2:
Input: A = 4, B = 3
Output: 4
Explanation: A + B + K = prime
K = 4, 4 + 3 + 4 = 11.So answer = 4
becuase 11 is minimum possible prime.
Your Task:
You dont need to read input or print anything. Complete the function minThirdPiles() which takes A and B as input parameter and returns the the minimum number of pens that should be there in the third pile so that sum of all three piles produces a prime number.
Expected Time Complexity: O(nlogn)
Expected Auxiliary Space: O(1)
Constraints:
1 <= A <=1000
1 <= B <=1000

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