Number by 3

The sequence of real numbers a[1], a[2],..., a[n] is given. Find the sum and the number of positive elements which indexes are divisible by 3.

Input

The number of elements n (n ≤ 100) in a sequence is given in the first line. Next line contains n real numbers, each value does not exceed 100 by absolute value.

Output

Print in one line the number of required elements and their sum with 2 digits after the decimal point.

Examples