For any two given positive integers p and q, find (if present) the leftmost digit in the number obtained by computing the exponent p^{q} i.e. p raised to the power q, such that it is a divisor of p^{q}.
Note: p^{q}^{ }may be a very huge number, so if the number of digits in p^{q} is greater than 18, you need to extract the first 10 digits of the result and check if any digit of that number divides the number.
Example 1:
Input: p = 1, q = 1
Output: 1
Explanation: 1 raised to the power 1 gives 1,
which is a divisor of itself i.e. 1.
Example 2:
Input: p = 5, q = 2
Output: 5
Explanation: The exponent 5 raised to the power 2
gives 25, wherein leftmost digit 2, does not
divide 25 but 5 does. Hence output is 5.
Your Task:
You dont need to read input or print anything. Complete the function leftMostDiv() which takes p and q as input parameter and returns the left-most digit in the number p^{q} which is a divisor of p^{q}. If no such digit exists, returns -1.
Expected Time Complexity: O(n)
Expected Auxiliary Space: O(1)
Constraints:
1 <= p , q <=50

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