#include int gcd(int a, int b) { if (a==0) return b; else return gcd(b%a, a); } int main() { int count = 0; for (int d = 5; d <= 12000; d++) { int lo = d/3+1; int hi = d/2; for (int i = lo; i <= hi; i++) { if (gcd(i, d)==1) count++; } } printf("%d\n", count); }