加强题解

#include<bits/stdc++.h> using namespace std; #define ll long long ll a,b,c,d; ll lcm(ll x,ll y){ return x*y/__gcd(x,y); } int main(){ cin>>a>>b>>c>>d; cout<<b-a-b/c-b/d+b/lcm(c,d)+(a-1)/c+(a-1)/d-(a-1)/lcm(c,d)+1; return 0; }