apps_876
Consider the function p(x), where x is an array of m integers, which returns an array y consisting of m + 1 integers such that y_{i} is equal to the sum of first i elements of array x (0 ≤ i ≤ m).
You have an infinite sequence of arrays A^0, A^1, A^2..., where A^0 is given in the input, and for each i ≥ 1 A^{i} = p(A^{i} - 1). Also you have a positive integer k. You have to find minimum possible i such that A^{i} contains a number which is larger or equal than k.
-----Input-----
The first line contains two integers n and k (2 ≤ n ≤ 200000, 1 ≤ k ≤ 10^18). n is the size of array A^0.
The second line contains n integers A^0_0, A^0_1... A^0_{n} - 1 — the elements of A^0 (0 ≤ A^0_{i} ≤ 10^9). At least two elements of A^0 are positive.
-----Output-----
Print the minimum i such that A^{i} contains a number which is larger or equal than k.
-----Examples-----
Input 2 2 1 1
Output 1
Input 3 6 1 1 1
Output 2
Input 3 1 1 0 1
Output 0
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