#include using namespace std; long long gcd(long long a, long long b) { if (b == 0) { return a; } return gcd(b, a % b); } int main() { long long t, a, b; cin>>t>>a>>b; long long g = gcd(a, b); long long l = a * b / g; cout<<(t-1)/a + (t-1)/b - (t-1)/l + 1<