阅读程序(1）
#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;
}
