7659: [CSES Problem Set] Counting Coprime Pairs
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Description
Given a list of $n$ positive integers, your task is to count the number of pairs of integers that are coprime (i.e., their greatest common divisor is one).
Input
The first input line has an integer $n$: the number of elements.
The next line has $n$ integers $x_1,x_2,\dots,x_n$: the contents of the list.
The next line has $n$ integers $x_1,x_2,\dots,x_n$: the contents of the list.
Output
Print one integer: the answer for the task.
Constraints
$1≤n≤10^5$
$1 \le x_i \le 10^6$
$1 \le x_i \le 10^6$
Sample 1 Input
8
5 4 20 1 16 17 5 15
Sample 1 Output
19