https://www.luogu.org/problemnew/show/P4213
#include<bits/stdc++.h> #include<tr1/unordered_map> #define fi first #define se second #define INF 0x3f3f3f3f #define fio ios::sync_with_stdio(false);cin.tie(0);cout.tie(0) #define pqueue priority_queue #define NEW(a,b) memset(a,b,sizeof(a)) #define lowbit(x) (x&(-x)) #define si(x) scanf("%d",&x) #define sl(x) scanf("%lld",&x) #define lc (d<<1) #define rc (d<<1|1) const double pi=4.0*atan(1.0); const double e=exp(1.0); const int maxn=6e6+8; typedef long long LL; typedef unsigned long long ULL; const LL mod=1e6+3; const ULL base=1e7+7; using namespace std; bool vis[maxn]; int mu[maxn],sum1[maxn],phi[maxn]; LL sum2[maxn]; int cnt,prim[maxn]; tr1::unordered_map<LL,LL>w1; tr1::unordered_map<int,int>w; void get(int N){ phi[1]=mu[1]=1; for(int i=2;i<=N;i++){ if(!vis[i]){ prim[++cnt]=i; mu[i]=-1;phi[i]=i-1; } for(int j=1;j<=cnt&&prim[j]*i<=N;j++){ vis[i*prim[j]]=1; if(i%prim[j]==0){ phi[i*prim[j]]=phi[i]*prim[j]; break; } else mu[i*prim[j]]=-mu[i],phi[i*prim[j]]=phi[i]*(prim[j]-1); } } for(int i=1;i<=N;i++)sum1[i]=sum1[i-1]+mu[i],sum2[i]=sum2[i-1]+phi[i]; } int djsmu(int x){ if(x<=6000000)return sum1[x]; if(w.count(x))return w[x]; int ans=1; for(int l=2,r;l<=x;l=r+1){ r=x/(x/l); ans-=(r-l+1)*djsmu(x/l); } return w[x]=ans; } LL djsphi(LL x){ if(x<=6000000)return sum2[x]; if(w1.count(x))return w1[x]; LL ans=x*(x+1)/2; for(LL l=2,r;l<=x;l=r+1){ r=x/(x/l); ans-=(r-l+1)*djsphi(x/l); } return w1[x]=ans; } int main(){ cin.tie(0); cout.tie(0); int T; cin>>T; get(6000000); int x; while(T--){ scanf("%d",&x); printf("%lld %d ",djsphi(x),djsmu(x)); } }
http://www.51nod.com/Challenge/Problem.html#problemId=1244
#include<bits/stdc++.h> #include<tr1/unordered_map> #define fi first #define se second #define INF 0x3f3f3f3f #define fio ios::sync_with_stdio(false);cin.tie(0);cout.tie(0) #define pqueue priority_queue #define NEW(a,b) memset(a,b,sizeof(a)) #define lowbit(x) (x&(-x)) #define si(x) scanf("%d",&x) #define sl(x) scanf("%lld",&x) #define lc (d<<1) #define rc (d<<1|1) const double pi=4.0*atan(1.0); const double e=exp(1.0); const int maxn=6e6+8; typedef long long LL; typedef unsigned long long ULL; const LL mod=1e6+3; const ULL base=1e7+7; using namespace std; bool vis[maxn]; int mu[maxn],sum1[maxn]; int cnt,prim[maxn]; tr1::unordered_map<LL,LL>w; void get(int N){ mu[1]=1; for(int i=2;i<=N;i++){ if(!vis[i]){ prim[++cnt]=i; mu[i]=-1; } for(int j=1;j<=cnt&&prim[j]*i<=N;j++){ vis[i*prim[j]]=1; if(i%prim[j]==0){ break; } else mu[i*prim[j]]=-mu[i]; } } for(int i=1;i<=N;i++)sum1[i]=sum1[i-1]+mu[i]; } LL Sum(LL x) { return x <= 6000000 ? sum1[x] : w[x]; } void DJ_shai(LL n) { for(LL i = n, y; i >= 1; i = n / (y + 1)) { y = n / i; if (y <= 6000000) continue; LL ret = 0; for (LL j = 2, l, pre = 1; j <= y; ++j) { l = y / j; j = y / l; ret += Sum(l) * (j - pre); pre = j; } w[y]=1ll-ret; } } int main(){ get(6000000); LL x,y; scanf("%lld%lld",&x,&y); DJ_shai(y); DJ_shai(x-1); printf("%lld",Sum(y)-Sum(x-1)); }