Given an array A of non-negative integers, the array is squareful if for every pair of adjacent elements, their sum is a perfect square. Return the number of permutations of A that are squareful. Two permutations A1 and A2 differ if and only if there is some index i such that A1[i] != A2[i]. Example 1: Input: [1,17,8] Output: 2 Explanation: [1,8,17] and [17,8,1] are the valid permutations. Example 2: Input: [2,2,2] Output: 1 Note: 1 <= A.length <= 12 0 <= A[i] <= 1e9