[BOJ 8291] Coprime Numbers
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Assembly, Awk, C, C++, Java, Pascal, Perl, Python, Sed, Text
Points:
4
Time limit:
5.0s
Memory limit:
128M
Problem types
Allowed languages
Two positive integers are said to be coprime if 1 is their only common divisor. Given a sequence of positive integers a1, a2, ..., an, find the number of pairs of its terms which are coprime.
입력 형식
The first line of input contains one integer n (1 ≤ n ≤ 1,000,000) denoting the length of the sequence. The second line contains n integers ai (1 ≤ ai ≤ 3,000,000).
출력 형식
Your program should output one integer representing the number of pairs (i, j) such that 1 ≤ i < j ≤ n and ai is coprime with aj.
예제 입력
5
3 6 4 7 3
예제 출력
6
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