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typedef __int64 ll; ll gao(ll l,ll r,ll n){//[l,r]内与n互素的数字个数 vector <ll> v; for(ll i=2;i*i<=n;i++){ if(n%i==0){ v.push_back(i); while(n%i==0)n/=i; } } if(n>1)v.push_back(n); int m=v.size(); ll res=0; for(int i=1;i<(1<<m);i++){ int cnt=0; ll val=1; for(int j=0;j<m;j++){ if(i&(1<<j)){ cnt++; val*=v[j]; } } if(cnt&1)res+=r/val-(l-1)/val; else res-=r/val-(l-1)/val; } return r-l+1-res; }