Given a 5x6 snakes and ladders board, find the minimum number of dice throws required to reach the destination or last cell (30^{th} cell) from the source (1st cell).
You are given an integer N denoting the total number of snakes and ladders and an array arr[] of 2N size where 2i and (2*i + 1)^{th} values denote the starting and ending point respectively of i^{th }snake or ladder. The board looks like the following.
Note: Assume that you have complete control over the 6 sided dice. No ladder starts from 1st cell.

Example 1:
Input:
N = 8
arr[] = {3, 22, 5, 8, 11, 26, 20, 29,
17, 4, 19, 7, 27, 1, 21, 9}
Output: 3
Explanation:
The given board is the board shown
in the figure. For the above board
output will be 3.
a) For 1st throw get a 2.
b) For 2nd throw get a 6.
c) For 3rd throw get a 2.
Your Task:
You do not need to read input or print anything. Your task is to complete the function minThrow() which takes N and arr as input parameters and returns the minimum number of throws required to reach the end of the game.
Expected Time Complexity: O(N)
Expected Auxiliary Space: O(N)
Constraints:
1 ≤ N ≤ 10
1 ≤ arr[i] ≤ 30

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