The number of Mersenne numbers#1354
A Mersenne number is a number of the form 2^n - 1, where is a natural number.
Given an array of integers, count how many numbers in it are Mersenne numbers.
The first line contains an integer – the number of elements in the array. The next line contains the numbers a_1, a_2, \dots, a_k. (0 < k < 1000, 0 \le a_i < 2^{31}).
Output a single number – the number of Mersenne numbers in the given array.
Example 1