现在感觉反演好多都是套路QAQ…… #include<bits/stdc++.h> using namespace std; ; typedef long long ll; int n,cnt,prime[N],phi[N],mu[N],vis[N]; ll ans,s[N],f[N]; void calcmu(){ memset(prime,,; memset(phi,,,sizeof(mu)); memset(s,,,sizeof(f)); mu[]=;phi[]=;memset(vis,…