二、阅读程序-1

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#include <algorithm>
#include <cstdio>
#include <cstring>
inline int gcd(int a, int b) {
	if (b == 0) 
        return a;
	return gcd(b, a % b);
}
int main() {
	int n;
	scanf("%d", &n);
	int ans = 0;
	for (int i = 1; i <= n; ++i) {
		for (int j = i + 1; j <= n; ++j) {
			for (int k = j + 1; k <= n; ++k) {
				if (gcd(i, j) == 1 && gcd(j, k) == 1 && gcd(i, k) == 1) {
					++ans;
				}
			}
		}
	}
	printf("%d\n", ans);
	return 0;
}