Product of Non-Zero Elements

You are given a list of integers. Your task is to compute the product of all non-zero elements of the list. In other words, if the list is \(a_1, a_2, \ldots, a_n\), then you need to compute

\(\prod_{\substack{1 \le i \le n \\ a_i \neq 0}} a_i\)

If there is no non-zero element in the list, output 1.

Note: Although the spirit of the problem encourages a solution without traditional loop constructs, you may use recursion or higher-order functions to achieve the result.

inputFormat

The input is read from stdin and consists of two lines:

• The first line contains a non-negative integer n representing the number of integers.
• The second line contains n space-separated integers.

outputFormat

Output a single integer to stdout which is the product of all non-zero elements of the list. If there are no non-zero elements, output 1.

This corresponds to the formula: \(\prod_{\substack{1 \le i \le n \\ a_i \neq 0}} a_i\) where the product is defined as 1 if the set of non-zero elements is empty.

7
1 2 3 4 0 5 0

120