莫比乌斯函数模版

const int maxn=1e6;const int mod=1e9+7;bool Mark[MAXSIZE];int prime[maxn];bool vis[maxn];int cnt = 0;int mu[maxn];int sum[maxn];int g[maxn];void Init(){    memset(vis,0,sizeof(vis));    mu[1] = 1;    cnt = 0;    for(int i=2; i<maxn; i++)    {        if(!vis[i])        {            prime[cnt++] = i;            mu[i] = -1;        }        for(int j=0; j<cnt&&i*prime[j]<maxn; j++)        {            vis[i*prime[j]] = 1;            if(i%prime[j]) mu[i*prime[j]] = -mu[i];            else            {                mu[i*prime[j]] = 0;                break;            }        }    } } for (int i = 1; i <= n; i++)      g[i] = f[i];  for (int i = 1; i <= n; i++)      for (int j = i + i; j <= n; j += i)          g[j] -= g[i];